# 96 GMC K2500 Transfer case Question



## fordmstng66 (Dec 27, 2005)

I just got a 96 GMC k2500 with a 4l80e trans, and i am having problems with the transfer case shifting hard. I replaced the fluid, and now it shifts better, and have 4low without grinding going into gear, and it will go into nuettral, but it does not seem that it is going into 4high, it will shift intojust does not seem to be in 4high Is it possible the switch on the transfer case is bad, or the actuator in the front axle? I am lost, because it does go into 4low. I am also planning on driving the truck for a little, then changing the fluid again, can i use a synthetic trans fluid in the transfer case? Truck is a 5.7 gas, with 150,000 miles on it. I did a search, and found nothing. Thanks in advance


----------



## Sydenstricker Landscaping (Dec 17, 2006)

Is it lever operated or push button?? Good possibility that the encoder motor on the transfer case is going out. When you put it in 4lo, are the front wheels engaged too?? Were there any metal flakes or shavings in the old oil when you drained it? If so, then there is an internal issue with the case.


----------



## fordmstng66 (Dec 27, 2005)

Lever operated. Yes the front wheels were engaged in 4lo. Yeah some shavings but not a lot, it was grinding when trying to shift into 4 lo a few times plus would grind going back to 2wd. It was low on fluid when I checked it and drained it.


----------



## Sydenstricker Landscaping (Dec 17, 2006)

fordmstng66;1027364 said:


> Lever operated. Yes the front wheels were engaged in 4lo. Yeah some shavings but not a lot, it was grinding when trying to shift into 4 lo a few times plus would grind going back to 2wd. It was low on fluid when I checked it and drained it.


Are you trying 4hi while moving or not?? Try rolling the truck real slow like 2-3 mph, put the trans in neutral and then try 4 hi. I think there is a way to adjust the shift linkage going into the tcase. Could be a possibility that it is out of adjustment. Otherwise it might be an internal mechanical issue


----------



## 2COR517 (Oct 23, 2008)

Are you positive the front wheels were engaged in 4Lo? Did you see them spin? Sounds like the front actuator may not be engaging.

Synthetic Manual Transmission Lube is the best fluid to run in that T-case.


----------



## fordmstng66 (Dec 27, 2005)

Tom thanks I will try that. I pulled the linkage off and cleaned up the ends that go into the nylon bushings I may need to buy new linkage, it is pretty rusty. 2cor yeah I can tell it is ingaged in 4lo because of how it rides.


----------



## 2COR517 (Oct 23, 2008)

fordmstng66;1027517 said:


> Tom thanks I will try that. I pulled the linkage off and cleaned up the ends that go into the nylon bushings I may need to buy new linkage, it is pretty rusty. 2cor yeah I can tell it is ingaged in 4lo because of how it rides.


Just because the case is in low range doesn't mean the front axle is engaged.


----------



## fordmstng66 (Dec 27, 2005)

I will have to find some mud and try that out. Thanks.


----------



## 2COR517 (Oct 23, 2008)

Just try a gravel road or driveway. You can test it in 4hi. I expect when you put it in 4hi and flatten it, just the rears will spin.


Wait.....is the 4wd indicator lighting up on the floor shifter?


----------



## Danhoe (Oct 15, 2007)

pm me I just went through the same thing. I have a K3500 1995 6.5l diesel, if it is a floor shift the forks on the shifter are toast, mine did the same thing and is on the hoist right now. Dan


----------



## fordmstng66 (Dec 27, 2005)

When engaged in 4lo it is, but when I shift to 4hi it does not.


----------



## Danhoe (Oct 15, 2007)

I just went through the same thing, hooked up the scanner you will get code 87 high gear ratio error. Everything works on the transmission. Your transfer case is in low range, it has to come out to repair it. Dan


----------

