NEWB HELP - Loose Pinion Shaft!!!

jrjarrett76 · 06-22-09, 03:02 PM

I am a new owner working through punchlist of PM items. I took my '91 to local Toyota service to do a once over on the rig and had a few things identified but the most glaring issue was stated as "REAR DIF PINION SHAFT IS LOOSE!" (also noted that pinion bearing is out, and right wheel bearing is loose)

Asked for more information as to what was the cause and what it would take to repair. Their answer of course was "we wont know until we get it apart..." The cynical side of me thinks they just wanted to get me for a rear axle rebuild because I am not noticing any drive issues. However, not knowing previous owner history, I think its best to do the work. I am prob a 1.5

mechanically. I have the FSM and bought this rig to expand on my skills so here goes nothing!

My goal is to build this cruiser to be a strong daily driver and wheeling rig and my approach is to get it mechanically sound before I add any extras. In the name of PM, I would rather err on the side of caution and replace parts that 'may' be damaged rather than have to do the job twice or wait for parts. My questions for the board are:

-What parts should I order to correct the stated problem of loose pinion shaft, pinion bearing, etc (I am assuming rear axle rebuild is going to be the overall project)?
-I do have vibrations and was planning on replacing U-joints soon, does it make sense to do this now?
-I may have answered my question as I type this....but is there a FAQ for rear drums? (I'll search the 60 forum as well)

Thanks in advance to all!

Jeff...

RedTacoma · 06-22-09, 03:47 PM

Take a part rear and check it out. I think people neglect rear axle and concentrate on front. I just did mine and was simpler that I have imagined. Plus I am glad I did since bearings were loose.

CJF · 06-22-09, 03:54 PM

Quote:

Originally Posted by jrjarrett76

-What parts should I order to correct the stated problem of loose pinion shaft, pinion bearing, etc (I am assuming rear axle rebuild is going to be the overall project)?

Whoa whoa whoa.

Do NOT assume they made ANY kind of accurate diagnosis. They easily may have just made up a bunch of complete BS; we've unfortunately seen it plenty of times.

I understand your thinking: "They said the problem was this, now I'll believe them but do the work myself." But...

Now that you've made the decision to do your own maintenance, you're MUCH better off taking it slow, reading up on here, and starting from scratch with your your diagnosing.

Welcome,

Curtis

phrogg4evr · 06-22-09, 04:05 PM

Quote:

Originally Posted by CJF

Whoa whoa whoa.

Yeah, what he said.

Go crawl under there and check your drive shaft, look for a lot of slop, or pull the drive shaft and check the pinion flange and stake nut for anything out of the ordinary. If that shit is all loose and buggered up, your pinion flange will have a lot of play in it.

Jack up the truck and do same with the wheel bearings.

What kind of vibes are you getting?

landtank · 06-22-09, 04:30 PM

I have had 2 rear diffs now with loose pinion bearings.

Did you have a lot of gear lube slung up on the passenger side upper control arm? That was apparent on both trucks with this problem.

I only broke down one diff and it looked to me that only the bearing needed to be replaced. There was some marring on the pinion shaft but I was able to determine that the bearing race had a slight taper to it.

Here is what I found when I opened one of them up.

jrjarrett76 · 06-22-09, 04:37 PM

Thanks for your replies... I am getting the loud whirrr and grrrs when UNDER POWER. From all I know and all I've read here those symptoms usually point to needing new U-Joints. I plan on replacing them all and having the DSs balanced at the same time. I don't have the play in the DSs that I expected but the U-joints do look pretty 'buggered up'.

My plan before going to Toyota was to replace U-joints, change all dif fluids, and then begin diagnosising any issues that come up. I think I can still stick to that I may have a few more days on jack stands than I had hoped. I got under the truck and yanked and pulled at the DS and there just isn't any noticable play in there on either side. The flange looks clean and sturdy and I don't have the oil splash on the passenger side. I've driven the truck for 1K miles and I'm sure even if the previous owner had cleaned it up I would have something by now.

The guy drove the truck for maybe 10 minutes and came back with the "PINION SHAFT IS LOOSE!" comment. Is there something that I'm missing when I drive the truck that would point me in that direction? I attached photos of the DS / Flange as well as a closeup of the U-Joint.

I'm still thinking I want to see whats going on in there and take it apart. The FSM notes some special tools that appear to be gear pullers. Are there any tools recommend for the rebuild?

Thanks again

Thoughts?

CJF · 06-22-09, 06:30 PM

Quote:

Originally Posted by jrjarrett76

The rear axle rebuild still seems like a worthwhile investment since I don't have a complete history and it is at 150K miles.

Shouldn't go to the top of the list unless YOU determine there's a problem, or you have unlimited funds to service every possible trouble spot.

Plenty of other things to baseline first on a rig with an unknown maintenance history.

CJF · 06-22-09, 06:33 PM

Quote:

Originally Posted by jrjarrett76

The guy drove the truck for maybe 10 minutes and came back with the "PINION SHAFT IS LOOSE!" comment. Is there something that I'm missing when I drive the truck that would point me in that direction?

I'll bet he's just unfamiliar with the amount of "normal" AWD drivetrain slop in a 91-92.

For example: How would he even determine from a test drive that it was the rear rather than the front?? (If it turns out you are in fact having diff. trouble, it's much more likely to be from the front.)

Lka1988 · 06-22-09, 06:44 PM

Didn't think of the clunk... The tech probably felt the typical 91-92 "clunk" and assumed that it was the rear pinion shaft. Did he physically try to move it by hand? or was it just his idea?

jrjarrett76 · 06-22-09, 06:53 PM

I don't have unlimited funds by any means... that said I'll go back to the GOOD advice I've gotten here. Its just hard to get it out of my head because it came from the Toyota guys.

Complete
-Oil & Filter
-Air Filter
-Fuel Filter
-Plugs, Wires, Coil, Cap & Rotor
-Exhaust Rebuild

To Do
-Power Steering Flush & Diagnostic
-Cooling System Flush
-Transmission Fluid Flush
-U-Joints

Thoughts on above list?

Lka1988 · 06-22-09, 06:55 PM

Now hold on a minute-

Just cause they work for Toyota doesn't mean they are experts on every Toyota model. Tech training usually just involves new models, not the older, quirkier ones (like the 91-92 FJ80).

jrjarrett76 · 06-22-09, 08:42 PM

I agree. I trust this board 1000X more than the guys I talked with.

You guys (and hopefully me one day) are the experts on these rigs NO QUESTION. I've been a take it to the dealer and write the check for a while. Its hard to shake but I'll do it with confidence with the support and info I've found here. Trust me I was worried that I was going to have to explain a 1K bill to the wife and not looking forward to it after my trip to the dealer. After advice from the board, I'll at least be able to spread that out over a couple of projects and put it towards parts instead of labor.

Thanks!