Mad amount of driveline slippage.

[Arnie897]

97 4.0 OHV, 5 speed, 4405 (control trac), EZ Locker in rear.

I'll be driving down the road and now the truck shifts from left to right during every part of my daily driving. It's dangerous because I'm all over the road and can't get a good hold of any type of acceleration. There is a horrible slipping noise.

It sounds like a locker problem so I started a thread a week or so ago and they all say it's normal. It can't be, I jacked up the rear of the vehicle and checked the locker for proper engagement/disengagement.

So I crawl under there and the check the driveshaft and replace all U-joints because I noticed some movement in the driveshaft when I shook it. I can twist the driveshaft about a 1/2 turn which I would imagine is normal. Although, there is about 1/2 inches of up and down movement where it attaches to my transfer case.

Is this loose connection to my t-case causing the horrible problems with my driving? How do I fix it safely and quickly? Do I need to have it towed somewhere for transfer case work?

Thanks,

Arnie

 

[merc2dogs]

could you clarify the up/down movement at the t-case? is it in the tcase bearing, or the driveshaft itself?

Should not be play either place, but I don't see where that would realy affect tracking.

assuming tire pressure is right, and alignment is good:

short visual/mechanical test, start it up, and with the brakes on lightly apply power with someone watching the tires and axles, have them look for any movement that shouldn't be there, it's normall for the truck to squat or lift depending on which gear (forward/reverse) but look for one tire moving ahead or back, if you see something like that check the bushings, or spring for that wheel. (test is good for most, but not 100%)

alternate, jack up each end of the truck, and see if you can move the tires ahead or back, a good kick or shove to the front and rear of each tire will show if there's any play in the bushings. slight movement is normal, anything over 3/4" is bad

also check tie rods, push and pull hard on front of tire, best is very little play, a lot of play means you have a bad tie rod end, also check the steering shaft.
check bearings in front by pushing and pulling hard on top of the tire, if they're bad you'll feel play, and maybe, depending on how bad they are hear a clunk.

check the springs on the rear end, make sure there are no broken leafs
there are other things that will make it wander, but those are the most common.


a locker will sometimes make itself known by a touch of wandering, but nothing major
as you describe.

Also, get on some loose gravel or sand and drive easily for a short stretch (50 feet maybe) in a slight curve, just enough so each tire leaves it's own track, then get out and look at the tracks, they should all be very very similar, if not, check the tire and suspension for that track. If 3 tracks show good tread pattern, and the fourth shows a smooth pattern (unless that tires bald!) that tire is dragging (bad brakes) or if one track is wider than the others, it means that tire is scuffing because of bad alignment if front, bent shaft or rim if on rear.

to check alignment if you don't have sand or light gravel available, take chalk and put stripes accross the tread, then drive in a straight line (NO TURNS!) and inspect the chalk, if alignments off it be rubbed off on one edge or the other, good alignment will have the same amount of chalk left all around the tire if you have a tire that shows no chalk on both edges at opposite sides of the tire, you have a bent rim or axle

ken.

 

[Arnie897]

First of all thanks Ken for your reply.

If the T-case has some sort of rear output bearing that would most definately be where the play is.

I can ride in a straight line until I have the slip so I'm not really having tracking problems, but when this loud slip occurs the whole rear of the vehicle will shift one direction or another.

All tires are practically new all around 35psi or so, recently alligned, springs/shocks are in good condition.

I just need to know if this slip is indeed the rear of the transfer case or if that is even possible.

 

[gijoecam]

By slip, do you mean that the rear of the vehicle actually steps out to one side and needs to be steered the opposit direction, and then it shifts back the other way, kind of like when you're doing a burn-out, or in 2wd in the snow/mud?

If so, then I suspect something's let loose in the rear.... maybe a spring mount, maybe a cracked leaf spring, maybe a busted shackle, loose U-bolt, etc, allowing the axle to shift fore and aft on one side.....

My best guess....

I highly doubt it's the locker as it shouldn't do anything when driving straight down the road. Cornering might be a little weird, but straight ahead it should completely normal. In fact, even if it malfunctioned, I don't see how it could cause what you're describing.

-Joe

 

[Arnie897]

Problem solved. It was the locker. All the teeth were rounded enough that it was almost like having a 1/2 open diff. It wouldn't go forward this morning so I broke down and took it to a shop. Thanks for everyone's help.

Arnie