Leaking, help.

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Smitch320

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I think I have maybe found the problem to my problem I posted about a while back.

I went under the truck to look at my power steering, which the high pressure line has busted, and I discover this.

I guess I need seals?

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The rear chunk is leaking at the yoke at the end of the drive shaft.

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I guess that is the yoke ^?
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That is the front U joint, of the rear shaft, which I am assuming is leaking from the T-Case.

Not to sure about all of this, honestly. Tell me what you think
 

Smitch320

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I figured since I had a manual trans, that the tcase would also have grease.

I guess not since I have red fluid leaking out :shrug:
 

mtnmankev

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If it's a chain drive transfer case, they use auto tranny fluid.
Gear drive T cases use gear oil.
 

marks86

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your pinion seal is shot..
 

lusktommy

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well i sure hope its a chain driven T case its gonna suck balls if that has been filled with tanny fluid and its gear driven..but in 86 if im not mistaken they came with a NP208 which is chain driven..so unless someone swapped it you have a chain driven NP208... and yeah pinion seal is definitely gone..my recommendation is to check the bearings too.. differential seals and bearing kits usually are to bad on price.. and that adds to one less thing to worry about.
 

Smitch320

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It is a 208. As far as the tcase leak, is that the rubber seal on the output shaft?

and the Pinion seal is the leak at the front of the rear chunk in the back?
 

Smitch320

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Hell, after thinking about my symptoms I bet I need a rear end. Vibration upon acceleration, vibration upon stopping after being on the interstate.

Taking this one to the mechanic.
 

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Maybe no way of really know unless you pull the inspection plate and see what you got. If it's vibrating and it is in fact coming from the rear end then. I'd definitely have it looked at for sure
 

Smitch320

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is 90w what came in these rear ends? I replaced the pinion seal and want to fill her back up before I put her back on the road.
 

89Suburban

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I've read on here about the front drive shaft yokes have a small hole bored through the center and sometime they leak there? I think it might have been @HotRodPC or @crazy4offroad. Been a while since I seen that post.
 

Smitch320

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This may sound dumb, but when replacing my pinion seal, I dropped the drive shaft, undid the 1'1/8 nut or whatever big ass size it was, and pulled the flange out and then popped the seal out with a pick, then popped the new one in, and made sure I had equal pressure from a 2x4 with a hole cut out so the seal was equally inserted, then finger tightened the nut, to where it was originally and then torqued to about 270 foot pounds.
IS that the proper way of going about replacing the pinion seal?

Any input appreciated.
 
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Smitch320

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Also, I think my rear end may be ok, while inspecting some of the old gear oil that that came out while replacing the seal, I saw maybe only 2-4 tiny tiny specs of silver. I am assuming I would have seen more.

Anyways, maybe this will keep me on the road a little while longer.
 

crazy4offroad

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This may sound dumb, but when replacing my pinion seal, I dropped the drive shaft, undid the 1'1/8 nut or whatever big ass size it was, and pulled the flange out and then popped the seal out with a pick, then popped the new one in, and made sure I had equal pressure from a 2x4 with a hole cut out so the seal was equally inserted, then finger tightened the nut, to where it was originally and then torqued to about 270 foot pounds.
IS that the proper way of going about replacing the pinion seal?

Any input appreciated.

No. The pinion has a crush sleeve between the inner and outer pinion bearings that set bearing preload. If it vibrates while driving now it more than likely did not get fully seated. If you wanted to go through it again you can pull the outer bearing and replace the crush sleeve, or hammer the old one on the horn of a vise to stretch it back out. Then reassemble and use a heavy duty air impact (at least 450 ft/lbs) to crush the sleeve and set preload. Preload should be around 25 inch/lbs rotational drag, which you can try to spin it and it should move freely but stop when you let go. Of course with the carrier in the axle this will be hard to get right, especially using the impact to crush the sleeve but I've done it, you have to take the rear cover off and try to hold the end of the pinion with a rag or stuff rags around it to reduce the impact being transferred to the ring gear which can chip a tooth.

The problem with just trying to tighten the pinion nut with a torque wrench or cheater bar, the pinion gear teeth will deflect off the ring gear teeth, and you think you got it tight but not really. The pinion will actually be slightly angled, and it only takes 0.005" to cause vibration and run out, and run out will knife the pinion teeth and junk the gear set. So if you're seeing silver in the diff oil you really should redo it or it will have a short life.

EDIT: Also you should take a hammer and cold chisel and knock a couple notches in the outer edge of the pinion nut. This is like making a locknut strong again. Also you need to put red high strength loctite on the pinion threads when running the nut down.
 

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