# 4L80e - Replace or Rebuild?



## 2COR517 (Oct 23, 2008)

Lost reverse in my 97 GMC 2500. 125,000 miles on it. I can have it rebuilt by an extremely highly recommended shop for about $2,000. Includes R & R and new torque converter. 12 months 12,000 mile warranty. 

Or...... new GM transmission. 3 years 100,000 mile warranty. Going to cost about $500 more, and at least a day of my time helping my mechanic friend put it in. I'm not sure if that price includes a new torque converter. Has anyone bought a new one and had to have warranty work done? Does GM reimburse my mechanic's labor? What would you do? If I need to buy a new converter, I am will most likely go with rebuild. Any input appreciated. Thanks guys.


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## carl b (Dec 28, 2006)

where are you finding one that cheap ? I just had mine rebuilt it was $1200 or $ 2200 for a used both 1 year warr.


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## 70monte (Feb 5, 2008)

I would go with the new one for only $500 more. Your warrenty is much better on the new one. The torque converter probably comes with the new one and if not, they are not that expensive.

Wayne


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## brad96z28 (Aug 21, 2005)

I would go with a jasper Usually best warr and They have been good! They also have 3 year 75 k mile parts and labor warr. We just put one in a cube van.


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## frozenokiewi (Dec 26, 2008)

*GM Tranny*

rebuild!!! after owning 6 chev's with the 80 series tranny...Have it rebuilt and tell the builder to "build" it. Heavy duty pump welded steel torque converter better clutch packs. Spend the money I had mine rebuilt in our 1995 at 100k and it has had a plow on it for 7 years and thats all it does. Just sold the truck with 316k on it never another issue. Call Phil at ATS in appleton, wi 920-733-1285 he has rebuilt two of mine and he can at least tell you what to request so you can beat the crap out of it and never give it a second thought. By a GM you will buy the same issues...they are good transmissions but not built for what we are doing, the torque convertes blow up, they get too hot and burn clutches we both know what we put these trucks through and GM did not build this tranny for that work out we give them. Take your tranny with its many good parts and upgrade the parts that take the abuse and you have the best of both words all be it without the 100k warranty. Find an honest shop talk to phil and go from there. Tell him Ryan with the white suburban told you to call, he will tell you exaclty what to ask for if you have it rebuilt. Good luck!



2COR517;690409 said:


> Lost reverse in my 97 GMC 2500. 125,000 miles on it. I can have it rebuilt by an extremely highly recommended shop for about $2,000. Includes R & R and new torque converter. 12 months 12,000 mile warranty.
> 
> Or...... new GM transmission. 3 years 100,000 mile warranty. Going to cost about $500 more, and at least a day of my time helping my mechanic friend put it in. I'm not sure if that price includes a new torque converter. Has anyone bought a new one and had to have warranty work done? Does GM reimburse my mechanic's labor? What would you do? If I need to buy a new converter, I am will most likely go with rebuild. Any input appreciated. Thanks guys.


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## brad96z28 (Aug 21, 2005)

And gm dont pay labor when it fails Ive been through that with them..


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## Spitz (Feb 28, 2008)

Wow that shouldnt even be a consideration. Gm's remans come with new converter.. I would put an aftermarket cooler in there if your doing any plowing or hauling as well. It takes make 30mins more and will really help the longevity of the transmission. Another thing to consider is if your trans goes out again, and your a lengthy distance from home, just take it to any gm shop, and actually some independant shops can do warrenty transmission work ( what we end up doing).. And yes, we do warrenty (part + labor claims) sometimes..


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## Sydenstricker Landscaping (Dec 17, 2006)

I would just rebuild it. That way you can have it built to how you drive and work it, not just plain jane out of the box. I would much rather have a nice heavy duty trans that is built with less warranty rather than have the same slushbox put back in with out the heavy duty crap. If my trans does ever go, it will get rebuilt with all heavy duty stuff (that way I can get rid of all the torque managment too)


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## 2COR517 (Oct 23, 2008)

Most likely going to go with the rebuild, for a few reasons. Money. It will be closer to a grand after I figure in my lost time helping install the new one. Work area. My friends garage is not big enough to fit my truck, so we would have to take his tools to another friends garage. PITA factor. All this running around, no shop, running around for parts we didn't realize we'd need, my busted knuckles, working on the floor, losing paying work, on and on and on. 

The guy doing the rebuild has a fantastic reputation. All the people I have spoken too either asked me if he is going to do it, or say he's great when I tell them. He's a close friend of a fellow I go to church with. Brand new shop, several bays, lifts, all that. 

The warranty has been the only sticking point for me. The 3 years would be nice. But, will GM be around in three years? Probably. Will they try to find any reason to not cover me? Probably. And I keep thinking of Tommy Callahan trying to sell brake pads in Tommy Boy. "All you're getting is a guaranteed piece of siht"


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## brad96z28 (Aug 21, 2005)

2COR517;691834 said:


> Most likely going to go with the rebuild, for a few reasons. Money. It will be closer to a grand after I figure in my lost time helping install the new one. Work area. My friends garage is not big enough to fit my truck, so we would have to take his tools to another friends garage. PITA factor. All this running around, no shop, running around for parts we didn't realize we'd need, my busted knuckles, working on the floor, losing paying work, on and on and on.
> 
> The guy doing the rebuild has a fantastic reputation. All the people I have spoken too either asked me if he is going to do it, or say he's great when I tell them. He's a close friend of a fellow I go to church with. Brand new shop, several bays, lifts, all that.
> 
> The warranty has been the only sticking point for me. The 3 years would be nice. But, will GM be around in three years? Probably. Will they try to find any reason to not cover me? Probably. And I keep thinking of Tommy Callahan trying to sell brake pads in Tommy Boy. "All you're getting is a guaranteed piece of siht"


Yep no faith in my sticking behind there products Ive had experience with a gm tranny that actually made a car catch fire:crying:. They will stand behind there product way behind it! I have had a problem with a jasper trans and they gave another tranny, paid labor, and even paid for new fluid.


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## 2COR517 (Oct 23, 2008)

Just thought I would update. Went with the local rebuild. Got to know the guys at the shop pretty well. Very happy with my decision. $1,900 all in - new torque converter, pressure manifold, cooler flush, and a few other goodies. Turns out the tranny in the truck was a GM Reman. It was in pretty good shape, the clutches had quite a bit of life left. We actually considered just repairing reverse. Went for the full rebuild. It was all out, would have been foolish considering how hard I work the truck. At least I have a little warranty. If you are familiar with these, the reverse band has two dogs that lock in the case, and one that the servo pushes. Usually the one dog breaks. Not mine. Both the the case side dogs split. The guy who rebuilt it had never seen that in 20 years. Clearly a defective part from day one, bummer for me. Also, there was some grooving on the overdrive drum where the clutches slide. Steel clutches pushing and sliding against an aluminum drum. No wonder GM had OD problems. Probably explains the occasional shudder I had going in and out of OD. Goes great now. The only big difference I noticed is the 1-2 upshift is a little quicker and firmer. Of course reverse works too, and 3-4 is smooth as silk. 

I have noticed my plowing style has changed a little. I try to make my runs longer, to reduce my reverse cycles. What's interesting is my failure had nothing to do with lack of maintanence or pushing hard on big piles, towing big loads, any of that. 20 coolers and a Double Atlas transfer case wouldn't have prevented the failure either. What we really need is a power reverser between the trans and T-case.....

Here's a little fuel for Ford vs. Chevy vs. Dodge fire. The guys at the shop all drive Fords, but they said the GM trannys are best. The bench guy said the 4L80e is the best tranny in any pickup out there right now. When they rebuild Fords they ALWAYS put in a shift kit, and ALWAYS put in synthetic fluid. They said I could do the same, but would be pretty much throwing money away. I think I will take it in to have the fluid changed in the spring. That way they can make there is nothing floating in the pan that shouldn't be. I will probably put in synthetic too, just because. Oh yeah, the bench guy said Dodge transmissions are the worst. By far. Cars, minivans, trucks, all of them. Especially trucks. Sorry guys. I have personally owned several high mileage Dodges, my father has too. No transmission problems for us. Go figure. None of them were plow trucks though.

Happy plowing everyone


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## CAT 245ME (Sep 10, 2006)

I have a 98 Silverado 2500 with the 4L80E that needed rebuilt back in november. The tranny was the origional and had 380,000 kilometers on it and has been a work truck since it left the dealer. 

The shop that rebuilt it said the same thing about the 4L80E, very strong but I think the strongest auto tranny is the TH400 but you cant go wrong with eathier as long as there properly built.

I've alway's said GM had the best auto tranny (TH400), best rear axle (14 bolt FF) and best gas engine (350ci) atleast from 2000 on back. But I wont comment on there trucks since the year 2000.


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## Baitshop (Dec 10, 2008)

GM remanufactured transmissions are done in Mexico last I checked. Have a reputable shop do it.

-Jared


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## Bigcat99 (Jan 7, 2009)

How can I tell what tranny I have in my '04 1500? Do all the 1500's come with the same tranny - excluding the SS versions?


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## Triple L (Nov 1, 2005)

I bet your got the 4L60E.... but i think it depends on the motor, does the 5.3 get the 80?


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## ghlkal (Dec 18, 2008)

2COR517;724441 said:


> Just thought I would update.


Thanks for the update ... I always appreciate it when folks follow up so I know what happened.:salute:



2COR517;724441 said:


> Here's a little fuel for Ford vs. Chevy vs. Dodge fire.


My experience bears this out too.


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## ghlkal (Dec 18, 2008)

Bigcat99;731454 said:


> How can I tell what tranny I have in my '04 1500? Do all the 1500's come with the same tranny - excluding the SS versions?


IIRC, the 1500 only gets the 4L60E. You need an HD or 2500 to get the 4L80E.


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## worldclasstech (Feb 6, 2009)

*4l80e*

4l80E's are a great transmission, the only problem are the retards who don't know how to plow, and throw the truck into reverse while still moving forward, resulting in breaking the low and reverse band. All to save alittle time. Plus people don't put the transmission in manual first when pushing a big load. By putting the transmission in manual low, the low and reverse band is locked and makes it practically impossible to slip. I see it all the time. 4l60E's are a good transmission, only problem, they are a little weak. They are not meant for heavy duty work like the 4l80E, thats why alot of plow guys with 1500 pick-ups have problems unless they baby them. Bottom line, if you use the brakes to stop the truck, wait for the range shift, and change your fluid regular, you should have no problems.


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## ghlkal (Dec 18, 2008)

worldclasstech;745561 said:


> By putting the transmission in manual low, the low and reverse band is locked and makes it practically impossible to slip.


I didn't know that ... this applies to the 4L60E?

I agree: stopping before shifting into reverse and changing the fluid are vital. I didn't realize shifting down to [1] instead of [D] would be better ...


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## Bigcat99 (Jan 7, 2009)

ghlkal;746152 said:


> I didn't know that ... this applies to the 4L60E?
> 
> I agree: stopping before shifting into reverse and changing the fluid are vital. I didn't realize shifting down to [1] instead of [D] would be better ...


For anyone using the tow/haul mode during plowing... wouldn't this (running in low 1) just be taking that a step further, there by eliminating any potential risk of slippage? Or am I missing something?


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## worldclasstech (Feb 6, 2009)

*tow/haul vs. manual 1st*

There are two different things going on when in tow/haul mode and in manual 1st in a 4l80 When in tow/haul mode, the PCM ups the line pressure in the transmission by changing the amerage to the pressure control solenoid resulting in a firmer/stiffer shift, to reduce silpage, and also extends the shift points so your RPM's are higher when the shifts happen. This helps when towing a trailer. When in manual first in a 4l80 the low and reverse band is applied to the reaction carrier assembly, helping with holding power. Also in manual second, the manual 2-1 band is applied to the direct clutch drum/housing boosting holding power there as well. The only band in a 4l60E is the 2-4 shift band. This band is applied in 2nd and 4th gear to the reverse input clutch housing/drum.


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## BigLou80 (Feb 25, 2008)

worldclasstech;745561 said:


> Plus people don't put the transmission in manual first when pushing a big load. By putting the transmission in manual low, the low and reverse band is locked and makes it practically impossible to slip. I see it all the time.


didn't know that and i have never done it. after 7 years and 160K and hundreds of hours of snow pushing I have had zero transmission problems.

I do try to stop before changing gears and the fluid gets changed every fall and the filter every spring well ahead of the scheduled maint interval.


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## bgingras (Jan 16, 2004)

Just had my 4L80E rebuilt on my 1995 2500. $1500 complete was the quoted price. Included new bands, new solenoids, new HD tourque converter, new planetary, new clutches, then there was the "upgraded" list, which I lost track of by the end of page 1. The shop that did it rebuilds them for the other local shops. He had the truck for a full 2 weeks, but admitted that since I wasn't in a rush he worked on it part time. He also said he "added some stuff" becuase I plow...not sure what he did, but my fuel mileage went up to 14mpg, and it feels great plowing! He also addressed some exhaust leaks while he has it, changed out a U joint, re-built the front drive shaft, etc....oh, and the bill was still $1500 when I picked it up.


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## ghlkal (Dec 18, 2008)

worldclasstech;746374 said:


> The only band in a 4l60E is the 2-4 shift band.


Thanks. No advantage for [1] versus [D] with a 4L60E.


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## jefferson (Sep 12, 2008)

CAT 245ME;724779 said:


> I have a 98 Silverado 2500 with the 4L80E that needed rebuilt back in november. The tranny was the origional and had 380,000 kilometers on it and has been a work truck since it left the dealer.
> 
> The shop that rebuilt it said the same thing about the 4L80E, very strong but I think the strongest auto tranny is the TH400 but you cant go wrong with eathier as long as there properly built.
> 
> I've alway's said GM had the best auto tranny (TH400), best rear axle (14 bolt FF) and best gas engine (350ci) atleast from 2000 on back. But I wont comment on there trucks since the year 2000.


The TH400 is a 4L80E.
4L80E electronic
400 not


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## 2COR517 (Oct 23, 2008)

jefferson;750446 said:


> The TH400 is a 4L80E.
> 4L80E electronic
> 400 not


Ahh, not quite. The 4L80e is a 4 speed overdrive transmission with full lockup torque converter, shifting and lockup is controlled by the PCM. The TH 400 is a 3 speed, no computer required. The 4L80e IS based largely on the TH400, and they do share some common parts. They are/were both used as GM's "Heavy Duty" transmission.


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## B&B (Nov 4, 2006)

2COR517;750619 said:


> Ahh, not quite. The 4L80e is a 4 speed overdrive transmission with full lockup torque converter, shifting and lockup is controlled by the PCM. The TH 400 is a 3 speed, no computer required. The 4L80e IS based largely on the TH400, and they do share some common parts. They are/were both used as GM's "Heavy Duty" transmission.


Glad you pointed that detail out. :salute:

As for using the manual first gear position to "add" holding capacity to either a 400 or 4L80E...

The only problem with that is the fact that the low/reverse band DOES NOT ADD TORQUE HOLDING CAPACITY in the forward direction. It's ONLY two purposes are to provide reverse direction (by holding the reaction drum stationary) and to provide compression braking in manual low..it serves no other purposes. If fact if you had no use for reverse or compression braking in manual second you can omit the low/reverse band and it will not in any way compromise the forward holding capacity of the trans. Same with the front band...its only purpose is to provide compression braking when manual seconds is selected and can also be omitted if that feature isn't needed. In fact, the front band in a 400/4L80E is often omitted for racing use to lessen the slight drag they create. Doesn't affect the clutch holding ability in any way.

Your far better to use tow/haul (if you have the feature) to add life to the trans than to falsely depend on the manual first gear position thinking that the rear band adds clutch holding ability. But the best reason to use manual first is to simply prevent the trans from unnecessarily up shifting when plowing small areas where the up-shift isn't necessary and slightly higher RPM's are wanted/needed, both for better alternator output as well as lessening converter slippage...which will lessen heat development as most of the heat generated in an auto trans (at low speeds) is due to converter slippage.


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## 2COR517 (Oct 23, 2008)

B&B - as usual, your posts are very educational. I think I am reading that when I put my trans into [1], it applies the reverse band. So - given that the reverse band is one of the weakest links in these trans, and I want to reduce my reverse cycles in any way possible, I should not use [1] unless I absolutely need it. I don't think I shift into second when plowing in HI Range, anyway. When I plow in LO Range, I usually shift to [2]. Now if only there were a way to make a foot switch to shift from [D] to [R]. My left foot is bored.


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## B&B (Nov 4, 2006)

The low/reverse band is applied in both manual 1st and reverse...which of course is the two gear positions you use the most while plowing. But in your case because your truck isn't T/H equipped your better to use manual 1st for two reasons...

1) To avoid the unnecessary up shifting like I mentioned.

2) The band will already be applied in manual 1st, so when you then shift to reverse, the band will only briefly be released and re applied. This helps to lessen the cycling on the band and its apply components since it's only very briefly released when you go from the manual 1st to reverse gear positions..or vice versa.

These low/reverse bands are the weakest link in a stock 4L80E's so anything you can do to ease the stress on it will prolong the time before the trans needs to come out. And it's not the holding ability (or lack of) that causes the band to fail, its the shock load placed upon it during apply, which physically breaks the apply anchor off the band. Which is also why they don't just slowly lose reverse, they lose it all at one time...since its not because it's slipping the band due to lack of apply force or psi, it's because it actually fractures the lug off it. Shifting into reverse while the tires are still turning in the forward direction is the quickest way to tear the lug off the band bar none. so thats a big no no as I'm sure your already aware.

If or when it finally does break or the trans simply tired and needs freshened up, thats the time to replace the weak stock OEM band with a HD aftermarket unit...thats all they need to solve the whole band issue these trans have. And the best aftermarket HD band that money can buy for a T-400/4L80E costs $50...but its the best thing you can do to add durability to it besides an aux trans cooler..


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## 2COR517 (Oct 23, 2008)

Guess I need to adjust my shifting technique to go all the way to [1]. Storm coming tomorrow night, I'll give it a try. I am also trying much harder to let the truck come to a full stop before hitting reverse. It's a bad habit and I didn't realize how much I did it until recently. Of course, I'm much more concious of my reverse cycles than I ever was before.


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## B&B (Nov 4, 2006)

2COR517;754809 said:


> It's a bad habit and I didn't realize how much I did it until recently.


Most guys don't realize it. And they're usually the ones who claim that they don't....because they don't even notice that they do...until it's too late. :crying:



2COR517;754809 said:


> Of course, I'm much more concious of my reverse cycles than I ever was before.


Then these forums are doing their job. wesport


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## CityGuy (Dec 19, 2008)

A little off topic but what exactly does the tow/haul mode do? From what I understand it changes the shift points. But does it do more than that?


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## B&B (Nov 4, 2006)

Not only does it raise the shift points (saving unnecessary shifts) but it also raises the line pressure, thus increasing clutch holding capability as well as modifying the torque converters locking/unlocking strategy.


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## 2COR517 (Oct 23, 2008)

Is it possible to add Tow/Haul mode to my truck?


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## B&B (Nov 4, 2006)

Would be a nice addition on an older non T/H equipped truck wouldn't it? Unfortunately the T/H works through the ECM and only the '99-up ECM's (Gen 3) are equipped to do so, so it's not a viable addition.


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## 2COR517 (Oct 23, 2008)

I know this thread is old, but I've been thinking, which is always scary. Anyway, if the reverse/low band is controlled electrically, why couldn't I add a switch to hold it? Kinda like a "plow/rock" mode.....


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## B&B (Nov 4, 2006)

2COR517;780739 said:


> I know this thread is old, but I've been thinking, which is always scary. Anyway, if the reverse/low band is controlled electrically, why couldn't I add a switch to hold it? Kinda like a "plow/rock" mode.....


While it sounds like good intentions and I like your thinking process it wouldn't be possible with a toggle switch because the rear band is actuated via fluid flow from the manual shift valve, not via the electrically switched valve assembly.

If it was possible it would also be a serious safety issue if you accidentally bumped the toggle with traveling down the road at speed (in 3rd or 4th gear for example) since it would then be engaged in two gears at once, creating instant carnage...or at the very least rear wheel lockup. Neither any good.


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## Mark13 (Dec 3, 2006)

B&B;780779 said:


> it would then be engaged in two gears at once, creating instant carnage...or at the very least rear wheel lockup. Neither any good.


Neither any good for the driver or passengers of the vehicle. But probably really cool to see happen standing a safe distance away.


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## sven_502 (Nov 1, 2008)

I may have missed this if its been mentioned but does the 4l60E have this same reverse band issue making it equally important to come to a complete stop as the 4l80E?


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## B&B (Nov 4, 2006)

It's important to stop the wheels before changing directions no matter what auto trans your running regardless...but to answer the specific question no, the 4L60E doesn't use it's single band for low or reverse, its only for 2nd and overdrive.

On those (the 4L60E's) when you abuse them by changing direction before stopping the wheels it usually tears the splines out of the reaction sun shell or it wipes planet gears out of the reaction carrier assembly as it's used for both low and reverse direction...and is where all the torque load is placed.

Notice I said "stop the wheels"..I didn't say stop the truck. If your good you'll know what I mean.


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## sven_502 (Nov 1, 2008)

B&B;781133 said:


> It's important to stop the wheels before changing directions no matter what auto trans your running regardless...but to answer the specific question no, the 4L60E doesn't use it's single band for low or reverse, its only for 2nd and overdrive.
> 
> On those (the 4L60E's) when you abuse them by changing direction before stopping the wheels it usually tears the splines out of the reaction sun shell or it wipes planet gears out of the reaction carrier assembly as it's used for both low and reverse direction...and is where all the torque load is placed.
> 
> Notice I said "stop the wheels"..I didn't say stop the truck. If your good you'll know what I mean.


Not that id do it, but I read somewhere on here that with the allison transmissions you can throw it in reverse while still rolling and it doesnt shift until its completely stopped? sorry to throw the thread slighlty off topic.


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## B&B (Nov 4, 2006)

Thats correct that it wont shift if the speed is too great as the Allison's have a great deal of protection built into them...but if your moving too fast you'll get a "range shift inhibited" message in the driver message center and the trans will default to neutral. You then have to shift to park and then back into gear to restore operation. 

Just Allison's way of protecting the trans from abuse. wesport


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## 2COR517 (Oct 23, 2008)

Well, I learned my lesson the hard way. It's amazing that I still catch myself not letting the truck fully stop.  But I do look for pull through parking spots at The Walmart. I still say a power reverser between the transmission and transfer case would be the ticket.....


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## sven_502 (Nov 1, 2008)

2COR517;781225 said:


> Well, I learned my lesson the hard way. It's amazing that I still catch myself not letting the truck fully stop.  But I do look for pull through parking spots at The Walmart. I still say a power reverser between the transmission and transfer case would be the ticket.....


True, but then why bother messing with an automatic if you've got that, just buy a 6 speed and have the best of both worlds.


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## M & MD Lawn (Aug 29, 2010)

subscribing for info


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## JimRoss (Sep 23, 2003)

So if you have the 4l80E and tow/haul mode, use that in conjuntion with the R-1-R-1 shift pattern?

And if I have the 4l60e, use the tow/haul mode and R-D-R-D shift pattern?


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## 2COR517 (Oct 23, 2008)

Always a good idea to go all the way to [1]. Saves shifting.


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