AUYota

I seem to have a leak from the area where the drive shaft meets the tranny. Some seal in the tranny I guess... Well the Runner is running very rough when moving in gear- simmilar to having bad u-joints but those are new. the whole body of the runner just above this area is covered in oil...

Please help... Thanks

FredTJ

Mmmm, you have a 4wd (according to your sig.) yet your driveshaft goes into the tranny ????
Auto or manual ?



Fred

AUYota

manual- well where ever the front of the drive shaft goes...

FredTJ

Front seal leak in the xfer case.
Check the fluid level for sure.





Fred

MudHippy

If you can feel any play when you grab the flange on that end of the shaft. If it wiggles a little, kinda like a bad u-joint, either the transfer case output shaft flange nut needs tightened or the bearing is bad. That would cause the seal to wear out quick, but they don't last forever. You definetely have a blown seal if there's gear oil slung everywhere. It's a cheap, easy, fix(the seal,not the bearing, it's cheap only). If you can turn a wrench your qualified, you'll need 90+ ft.lbs. of torque behind it to get the 30mm nut tight when your done.

AUYota

MudHippy,
Would this issue cause the runner to run very rough?

FredTJ

So the engine is running rough also, or are you just talking about the vibration that you get from the driveline (as you're talking about in your other post) ?
If it's driveline vibration then please be clear here on this thread.
If it's driveline vibration it's almost certainly related to your pooched xfer case seal (and possible bearing).




Fred

AUYota

sorry-
Engine purs like a kitty- the runner also is very smooth rolling in nuetral. All my problems are in the drive shaft and it's not u joints- those are new. I crawled underneath and saw a lot of slung up grease and oil just above the front of the rear drive shaft where it begins. I'm thinking a bad seal or bearing in there but am not sure how to replace those...

FredTJ

Crawl under it and push up on the driveshaft with your hand, right were it attaches to the output flange of the xfer case and let us know if it (the driveshaft/flange) moves upward.




Fred

MudHippy

Yeah, it will simulate a bad u-joint there at that flange by lettings things wobble around, vibration city. Either the flange nut being loose or the worn bearing. I've experienced all three on my truck, felt basically the same when driving. Rear driveshafts are my nemesis. Replacing the seal is a piece of cake(shouldn't take more than 45 min tops), the bearing on the other hand, is QUITE a chore. Somebody has a write-up for doing the transfer case rear output shaft seal, rock-auto or napaonline has the seal cheap. I could tell you what's involved with the bearing, if your curious.

AUYota

i crawled underneath and I played with the drive shaft. I can rotate the drive shaft a few degrees both ways- it has some play- which is bad. But I cant move it "upward." just has some play

Hippy,
Where is that write up?

MudHippy

Rotational play is o.k., if it won't wiggle side-side/up-down, the bearing is good and the flange nut is tight. I found that write-up, it's the same operation for the seal your needing to fix, this one is at the other end of the driveshaft, the flanges and nuts are interchangeable(both are called a companion flange, technically). And yes, the transfer case has a breather, so check it first. Ignore the pre-load comment in there, doesn't apply. Just torque the 30mm nut to at least 90 ft.lbs. when your done. I don't re-stake mine, I use blue loctite thread-locker.

http://4crawler.com/4x4/CheapTricks/...eal/index.html

AUYota

So we can assume it's the seal? So a bad seal will cause the drive shaft to run rough? How so? Oh and where is the transfer case breather?

MudHippy

That's a good question. The angle I'll approach from starts with the seal failure and it's cause. It's likely that heavy vibration in the driveline (somewhere) could cause it to leak. I have actually had the seal on my front axle pinion flange stop leaking after a bad vibration issue was remedied.

So, what I'm sayin' is it ain't the seal. I have to dig up a post from a few months back. I listed 15-20 different possible causes for driveshaft vibration. Most come from personal experience in my quest for victory over my previously mentioned arch-enemy, the rear driveshaft.

AUYota

yeah the drive shaft is beast- you are containing all those rpms to a very smooth contained motion- there is a lot that can go wrong.

MudHippy

Here's that thread, the last post there has the list as it stands. There's probably a few things missing from it, unfortunately.

https://www.yotatech.com/forums/f116/real-bad-vibration-107655/

The breather is there, somewhere. I'll go check where mine is.... O.k., strike that, NO BREATHER for the transfer case, at least not for VF1A(mine). I did find one located directly next to the transfer case shifter input, but I'm fairly certain in only vents the compartment between the transmission and the transfer case where the input/output shafts connect. I knew I remembered seeing one somewhere when I was rebuilding my transfer case, appearently not actually on the case itself.

AUYota

ok I took it to the shop and they said that the u joint "holes" are wobbled out and not allowing the u joint to fit snug. They are sending the shaft in for rebuilt... should be fun.

MudHippy

Adding it to the list. I hadn't thought of that one yet.

I have replaced my rear driveshaft twice now. It's a little harder to come by than a 4Runner shaft. They cost me $150 each.

AUYota

For that price you could have just rebuilt them? That's what I'm gonna do... he's saying 250-350 out the door labor and all. And it's good for a nother 235k

MudHippy

Yeah, I'm gonna have to from here on. I found a good driveshaft shop about 35 miles from me in Portland. Man, there ain't alot of those near me. Anyway, that's about 100 miles closer than the closest used rear driveshaft for my truck.