Ilovemountains

My 82 Trekker has a bad vibration, tonight I put the trans in neutral, along with the transfer case, jacked the rear end up and climbed under to see if the drive shaft or U joints were the culprits. The good: The original owner must have kept the joints and all lubricated on schedule, the bad the rear end has a LOT of slop on the input. Its not leaking fluid though............. Does the input flange bolt onto the rear end input shaft or do you all think my input / pinion bearings are shot???? I have not dropped the drive shaft to see if there is a big nut or something hiding behind it so excuse my ignorance but any help would really be great in case I need bearings or an entire donor 3rd member Id like to know so I can still back her out of the garage and all, Im hopeful that something is just loose, not bearings etc!!!!

Gov't Mule

When you say slop, are you talking about rotational slop or lateral slop? To answer your other question, yes there is a pinion nut that secures the DS flange to the pinion shaft. I doubt that that nut is loose though. More than likely either your pinion bearings are toast and the pinion preload is not in spec or if you have alot of rotational slop then your backlash is outa spec which could be either bad pinion bearings, bad carrier bearings, damaged ring and or pinion gear or all of the above. Tear into it and see what's up. I'm doing that to my '82 Trekker right now too because I'm re-gearing it to 4.88s for 33" tires. There is a buttload of info out there on Toyota 3rd member rebuilds...let me know if you need some good links.

Ilovemountains

Thanks for the reply! My rotational slop seems OK, no more than my 88's rear end, the 82's on the other hand feels like the entire rear input shaft is loose, I can move it up, down, left and right.... I'm going to drop the drive shaft tomorrow after work and see if the pinion shaft is just loose or if the bearings are toast, which Im hoping isnt the case! The U joints feel better than my 88's, Im quite sure that my 82 was well maintained by the original owner, he had it from 82 to 1999 or 2000 and mechanically is shows!!! The rear end is quiet compared to the original rear in my 88 that I swapped out this past summer, I bottomed out my rear drive shaft and trashed the input bearings, then drove it for another 50,000 miles like that It had a nasty howl, the 82 doesn't, it just has a vibration.....wish me luck thats she is just loose! If it is "tight" but loose does that mean the outer bearing is shot or both inner and outter, which case it would be easier to find an entire good rear 3rd member for me rather than tearing it apart as I dont have the tools to set up a rear end.... Thanks again for any ideas or input!!!!!! Ill definitely post what I find after I drop the D. Shaft!!!!!!! ~Matt

Gov't Mule

Matt,

The pinion nut gets torqued to a set value to achieve the proper pinion bearing pre-load. This pre-load is obtained one of two ways:

1) A "crush sleeve" is used on the pinion shaft between the inner and outer bearings that compresses and "crushes" while torquing the pinion flange nut to reach the proper pre-load value. If the flange takes a hard strike after the proper pre-load is achieved (like during rock crawling, etc.) it can actually crush that sleeve even further and completely diminish the proper pinion bearing pre-load. Therefore, tightening your pinion nut further to try and reduce the slack will do nothing but destroy your bearings (if they arent already).

2) Toyota also used a solid spacer with shims in lieu of a crush sleeve in their earlier model trucks. My 82 has these. These solid spacers basically let you torque the pinion nut to a set value (150 ft. lbs.) and end up with a pinion bearing preload of approx. 14 in. lbs. These solid spacers also resist tolerance changes if/when the pinion flange takes a beating out on the trail.

Check out this sight...it will give you alot of insight on these toyota 3rd members: http://gearinstalls.com/

This guy knows his stuff!

If I lived a little closer, I'd be happy to help you tear it down and rebuild it. It really sounds to me that that is ultimately what you're gonna need to do.

Feel free to PM or post with any other questions!
Pat

4Crawler

iTrader: (3)

You can usually get by by re-torquing that pinion flange to about 90 ft.lbs. and re-staking the nut if it simply loosened up. The torque needed to "crush" the crush sleeve is upwards of 130 ft.lbs. so staying below that will usually do the trick. I did that 3-4 times on my old rear diff (crush sleeve w/ Detroit locker) as it would loosen up from time to time. Ended up putting about 1/4 to 1/3 turn on that nut before it finally stopped loosening up.

- http://www.4crawler.com/4x4/CheapTri...eal/index.html

Ilovemountains

4Crawler, you called it! I dropped the drive shaft and the rear input nut was 1/2 turn loose, I cranked it to 90ft lbs and re-dimpled the nut... While I was at it I dropped the front of the shaft and the output from the transfer case was a little loose... There is still some bearing slop in the transfer case but for now I'm not even worried about it, I took it for a spin and 90% of the nasty vibration / noise is gone... I looked for the alignment marks on the drive shaft because it looks like it should be out of phase but couldn't find any so I just bolted it back in place... I need to take another look at the pictures to see if that's the reason its still having some vibration but as a whole its running pretty good!

4Crawler

iTrader: (3)

You can sight along the u-joint bearing caps to check for proper alignment/phasing:
- http://www.4crawler.com/4x4/CheapTri....shtml#Phasing

They should line up as indicated by the light blus line:

Ilovemountains

Its definitely out of phase then, Ill drop it again this evening and turn it, Im wondering how they come out of phased, the bolts / nuts on the drive shaft looked like they have never been touched!

Gov't Mule

How many miles are on your Trekker??

Ilovemountains

It turned 170,000 the other night when I took it out for a while, it has 18,000 less than my 88

Gov't Mule

My Trekker just turned 140K. My 2wd truck is at 276K. Awesome yotas.

Gov't Mule

Mine was out of phase almost 90*. It happens when people turn wrenches that shouldn't.