# Lost reverse 4l80e



## dheavychevy38 (Nov 19, 2008)

Now I have done some research and most if not all post say reverse band is the number one reason to lose reverse. I have done the engine brakeing test and that seem to be good from what I can tell I have to double check that as soon as some one can pull me out of the driveway lol. This trans has around 30000 on a rebuild. My question is what are the chances that the reverse servo is just bad and what are the chances that it wasn't up dated in the rebuild ?


----------



## tac48 (Jun 22, 2010)

Yes, reverse band failure is #1 reason for no reverse. The servo is definitely a possibility. You can pull it out and check it with pan removed, may need to loosen or remove valve body to get the servo cover off. Once the servo is out, you can manually apply band and try to tell if it is broke. Also, with pan off you can see if any debris in the pan indicating internal failure. If the direct clutch is burned up, it can cause no reverse but usually will slip or not have 3rd too! Hard to say what was done went it was rebuilt, everyone has their own ideas and ways of rebuilding. Hope this helps ya.


----------



## dheavychevy38 (Nov 19, 2008)

Ya she getten a full rebuild for 1900 $ and I'll have it back tues night. I think thats fair seeing as no other trans shop would look at it till mid to end of the week.


----------



## dheavychevy38 (Nov 19, 2008)

Does anyone have a suggestion for a stronger reverse band that I should recommed to the trans guy ? The funny thing is I always come to a complete stop and shift reverse to first and swich.


----------



## woodchuck2 (Dec 4, 2010)

I do not know much about this but i do know this tranny came behind the Duramax in the vans and is a common swap when installing a Duramax in a car or small truck. From what i have read this tranny can be rebuilt with heavy duty parts to hold up to a mildly tuned diesel so this may be the route you may want to take for your rebuild. Look into Suncoast or ATS transmissions for any tranny part upgrades.


----------



## woodchuck2 (Dec 4, 2010)

It appears Suncoast may be the one to go with if you want to go this route
http://www.suncoastconverters.com/gmc/gm_products.html


----------



## BlizzardBeater (Aug 29, 2010)

I dont know what prices are in your are but have you checked with the dealer on how much it would be for a factory reman 3 year 100,000 mile unit. I've bought several for less than that. I bought one 4 yrs ago for $1400. I think the last one was $1750.


----------



## woodchuck2 (Dec 4, 2010)

BlizzardBeater;1140345 said:


> I dont know what prices are in your are but have you checked with the dealer on how much it would be for a factory reman 3 year 100,000 mile unit. I've bought several for less than that. I bought one 4 yrs ago for $1400. I think the last one was $1750.


X2, even if the price is a few dollars more the longer warranty would be worth it. I know a fella who just bought a new Allison from GM cheaper than having his rebuilt.


----------



## Rex in OTZ (Nov 3, 2010)

*Tranny ?*

Work had a 96 F350 #2 tranny went out after 2 years, the cost of OH .vs replacement was a issue, they surplused the truck due to age, I had talked toa transmission shop they asked what the truck was used for? snowplowing in subzero temps, I was asked if the system was flushed of contaminants, the coolers removed and cleaned, asked I I was interested in installing a shift kit($200), if the truck had a heavey duty torque converter($400), In the end management went with a 2009 Chevy 2500 HD to mount the 8' Boss V smart hitch to, the nagging question still remains new truck that is supposed to be a plow truck, yes it has heavy springs up front, and a hole in the fire wall for plow wireing, even provision for strobe and backup alarm, but does it have a heavy torque converter? and shift kit?, reinforcement plates up front where the frame can crack? 
For plow trucks they should have dual batteries and heavy duty alternator, extra windo heat for rear(crew cab), heated wipers, and adiquate plowing mirrors instead of the std postage stamp ones they come with
Plow trucks off the dealer lot are just std trucks with minimal add-ons (beefed springs and firewall hole) the transmission is the key, without it you dont get work done.
As a truck with a automatic transmissionwhich has a transmission cooler core, is it a regular coolent core? or a larger one for towing trailers or in my case plowing snow? You know pushing snow builds lots of heat the tranny has to cool off, is it possible to install a transmission fluid temp gage? in the Mfg case a idiot light comes on when its hot?


----------



## BlizzardBeater (Aug 29, 2010)

Rex in OTZ;1140927 said:


> Work had a 96 F350 #2 tranny went out after 2 years, the cost of OH .vs replacement was a issue, they surplused the truck due to age, I had talked toa transmission shop they asked what the truck was used for? snowplowing in subzero temps, I was asked if the system was flushed of contaminants, the coolers removed and cleaned, asked I I was interested in installing a shift kit($200), if the truck had a heavey duty torque converter($400), In the end management went with a 2009 Chevy 2500 HD to mount the 8' Boss V smart hitch to, the nagging question still remains new truck that is supposed to be a plow truck, yes it has heavy springs up front, and a hole in the fire wall for plow wireing, even provision for strobe and backup alarm, but does it have a heavy torque converter? and shift kit?, reinforcement plates up front where the frame can crack?
> For plow trucks they should have dual batteries and heavy duty alternator, extra windo heat for rear(crew cab), heated wipers, and adiquate plowing mirrors instead of the std postage stamp ones they come with
> Plow trucks off the dealer lot are just std trucks with minimal add-ons (beefed springs and firewall hole) the transmission is the key, without it you dont get work done.
> As a truck with a automatic transmissionwhich has a transmission cooler core, is it a regular coolent core? or a larger one for towing trailers or in my case plowing snow? You know pushing snow builds lots of heat the tranny has to cool off, is it possible to install a transmission fluid temp gage? in the Mfg case a idiot light comes on when its hot?


GM 3/4 tons come factory with tranny temp guage in cluster, lower left hand corner. I got lost in the relevance of the rest of this post though. I dont think i've ever seen a duramax/allison combo without tranny cooler. They might exist, i really dont know, but i've never seen one.


----------



## Rex in OTZ (Nov 3, 2010)

*Tranny coolers*

My question is do they offer a bigger than stock oil cooler?


----------



## BlizzardBeater (Aug 29, 2010)

Rex in OTZ;1141146 said:


> My question is do they offer a bigger than stock oil cooler?


Absolutely. There are many fine aftermarket coolers designed for heavy duty use and yes they will definatly help with tranny life and cooling. And dont forget on every tranny replacement that all lines and coolers should be flushed out to keep from contaminated fluid from reaching the new tranny.


----------



## Gibsonk (Dec 8, 2010)

I don't know how hard you guys are on stuff but the Allison dealer here has never had to replace an Allison 1000 tranny thats behind the duramax yet. They have repaired wiring and such but never a compelte replacement. So ive been told by them and they are pretty good stand up guys.


----------



## damian (Jan 29, 2009)

tac48 is right,everyone has their own idea as to what constitutes a rebuild,as a longtime trans rebuilder myself it is impossible to remanufacture a modern automatic in the shop,pump halves need to be made flat,valve body bores get loose and need bore repairs with oversize valves,geartrains need rebush and true bore,pinon gears need needle bearing kits,parts upgrades and valve body calibration,dyno tesing,you just cant do it on the bench cost effectively.sure you cant take it apart,clean it,paper, rubber,ring,seal and friction it,maybe a bushing or two and put it back together but you never really fixed it.so many of my customers opt for the bench overhaul instead of a reman unit and end up paying twice after 12mo 12000mi.


----------



## damian (Jan 29, 2009)

a jasper reman 4L80E is around 2200 plus install and fluid,3 year 100000mi warranty it can be 3000 before youre done but it is a well done updated unit from a good stand up company that wont run you if you do have a problem


----------



## 2COR517 (Oct 23, 2008)

A simple way to lengthen the life of your reverse band is to change your shift pattern. Rather than [D] - [R] - [D] - [R] which continuously applies and releases the low/reverse band, use [1] - [R] - [1] - [R]. This will keep the band applied, greatly reducing the stress cycles. It takes a while to get used to it, but it's worth the effort. A couple of other advantages to this shift pattern is that it will keep the engine revs up. Allows the alternator to keep the battery charged better, and improves flow through the cooler circuit of the trans.


----------

