[Inferno]

Let me preface this by saying that I know next to nothing about four wheel drive setups. I do quite a bit of wrenching, but its always been on bikes and fast cars.

Anyways, I just picked up an '88 Suburban with a 6.2L Detroit diesel and a NP208 transfer case (not sure on the trans, but I'd assume its a 700R4). The previous owner said under hard braking it'd pop out of 2wd. Well, I finally got the brake lines fixed and went to test it out, and it pretty much jumps out of 2wd any time you even attempt to drive it. When this happens, you can't get the transfer case into any gear, and shifting the transmission doesn't do anything (it does grind if you try to go into park). The only way to get the vehicle to move again is to shut it off, put it in 4 low, and restart it. It'll work fine in 4 low and the 4wd works, and sometimes it'll let you go back into 2wd, but not always.

I tried adjusting the linkage a bit. I adjusted the nuts on the linkage about a 1/4" towards the front of the truck on the transfer case shifter rod, but it didn't help.

Any ideas? This thing is supposed to be my daily driver so I need it back on the road as soon as possible. Thanks.

 

[atvextreme]

1 of 2 thinks , either the linkage is popping it out or the shift fork internal to the 208 is worn.(their are pads that wear out)

I would elimiate the linkage and disconnect it first. then manually put it in to 2hi. (level ground, trans in neutral, shift it back to 2hi, might have to spin the yoke a little to get the teeth to alighn.)

try driving it.

if it slips out, it's time for a rebuild or replacement.

 

[Inferno]

Thanks for the advice. I'll give that a try and see what happens.

 

[Inferno]

I disconnected the linkage and manually put the transfer case into 2wd. It drove fine in 2wd until I got on the brakes kinda hard, which caused it to pop out. Time to rebuild/replace the 208?

 

[atvextreme]

Yeah, their fairly easy, once you open the case, you will notice the fork and the pads were referring to. if it's worn down enough the pads are long gone and the forks are needeing to be replaced also.

with parts in hand it's only a few hours. if you plan on ordering what you need, you won't know until it's inspected.

Might also want to just pick up a 241, but do the research, I'm not positive if it's a direct bolt in.

 

[Inferno]

Well I've got another '88 Suburban sitting here with a blown trans, but it does have the NP208 in it. The only difference is that one has the 350 in it. Would that transfer case work fine with the diesel drivetrain or are there differences?

As for upgrading, I'm not worried about that right now. Next summer this thing will have a completely different drivetrain, I just need it drivable for now so I have a winter vehicle.

 

[gigglestick383]

the transfer case will bolt right in out of the other suburban it does not matter if one is gas or diesel

 

[Inferno]

Awesome. That's what I thought, but I just wanted to make sure before I tore them both apart. Hopefully I'll have this thing back on the road soon.