daylton
1/2 ton status
So after i take my truck out of 4x4
its still lunging forward like its in 4x4
any ideas how to fix this?
its still lunging forward like its in 4x4
any ideas how to fix this?
CK5
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88 Jimmy Stuck in 4x4
- Thread starter daylton
- Start date
Auto hubs or manual?
daylton
1/2 ton status
auto hubs
Most likely the auto hubs are trashed. They are great when they work, but most of the time the do not. I would jack up the front axle, if the auto hubs are unlocked each side should spin independent from each other, and not spin the driveshaft. If the driveshaft spins thats your problem. Now you could also grab the front drive shaft, if its in park and still be able to spin free if the hubs are unlocked and the tcase is in 2hi. If when you have the front in the air and the driveshaft can not be turned, the tcase is still locked in.
88 should be a 208, so no full time. i'm sure martin will chime in to correct me if I am wrong.
daylton
1/2 ton status
Okay, ill try that tonight. ill post up what i came up with.
I think it's a np241 t case
daylton
1/2 ton status
88 can be either one, and sadly i do not know how to tell the difference of which one..
i only know 203 and 205...
i only know 203 and 205...
I know 89 was mechanical, 90 was electrical speedo. No clue on 88
Just crawl under tonight and look at the tag.
should be a 208 that's what my 88 had ...had to find an 89 when I switched to the 241
The hubs being locked or unlocked shouldn't cause this type of issue unless the front diff is a spool or maybe a real aggressive limited slip.
To the OP, how far did you drive the truck after shifting back into 2wd? If you just stopped, shifted the t-case, and drove forward 5' with the wheels turned it might not immediately disengage if the drivetrain is in a bind.
To the OP, how far did you drive the truck after shifting back into 2wd? If you just stopped, shifted the t-case, and drove forward 5' with the wheels turned it might not immediately disengage if the drivetrain is in a bind.
True or he could have steering out of alignment. I had a bad balljoint cause a similar effect when I was open.
My 88 has a 208. There should be a round tag riveted to the T-case facing the rear driveshaft.
If it's still truly in 4wd, then your hubs have to still be locked. As mentioned above, figure out why your hubs are still locked. If the wheels spin freely, but the front driveshaft cannot spin independently of the rear, then your t-case is still in 4wd. I would check linkage first at that point.
If it's still truly in 4wd, then your hubs have to still be locked. As mentioned above, figure out why your hubs are still locked. If the wheels spin freely, but the front driveshaft cannot spin independently of the rear, then your t-case is still in 4wd. I would check linkage first at that point.
I thought you were to stop and backup to unload the stress on (auto locking) on the hubs. I have an Auburn in front and if I lock the manual hubs, I have to put it in 4hi to be able to steer.
daylton
1/2 ton status
it did this last night and i drove it to work and same issue still. i have to look tonight
its like trying to lunge (thats how i can best describe it) like it wants to be in 4 wheel but doesnt.. not quite sure. but ill look tonight (i do know i need to drain/fill the diffs)
havent done it yet since i bought it (bout 2 weeks ago) and it has a small leak (could this be an issue)
its like trying to lunge (thats how i can best describe it) like it wants to be in 4 wheel but doesnt.. not quite sure. but ill look tonight (i do know i need to drain/fill the diffs)
havent done it yet since i bought it (bout 2 weeks ago) and it has a small leak (could this be an issue)
daylton
1/2 ton status
so jacked up the front checked it all out, auto hubs are okay now, my tcase checked good and bad..... sometimes it was letting me shift out of 4x4 and neutral and sometimes it was not..... im finding reversing before I go into neutral helps but still isn't perfect
I'm still confused on how a truck lunges forward in 4x4.
Now low range can make it jerk forward and slam you with the tranny shifts. But just being in 4x4 feels almost the same as 2x4 except when you're turning. Is that what you're talking about - the jerking motion from trying to turn tightly on a hard surface in 4WD? You pretty much need both hubs locked AND the T-case engaged for this to happen. Unless you have a front locker - then you just need 1 hub engaged AND the T-case engaged OR both front hubs engaged.Or is the T-case going into neutral and then grabbing?
Either way if the T-case isn't changing modes correctly you'll want to adjust the linkage. If that still doesn't make it reliable you probably have worn shift forks. This is common and happens to all of them eventually.
daylton
1/2 ton status
yeah, exactly when turning that jerking motion but it was doing it constantly, but now its fixed I messed with the linkage and seems to be the fix. 
FYI. The legit way to properly adjust linkage...
http://www.fullsizechevy.com/forum/.../491925-1982-k10-suburban-4x4-adjustment.html
http://www.fullsizechevy.com/forum/.../491925-1982-k10-suburban-4x4-adjustment.html
All 1988's have NP208's.
NP241's came in 1989-1991.
Doesn't matter anyway, they are basically the exact same thing.
Buy a set of lockouts and throw your automatic hubs in the iron pile.
Martin
NP241's came in 1989-1991.
Doesn't matter anyway, they are basically the exact same thing.
Buy a set of lockouts and throw your automatic hubs in the iron pile.
Martin
