3rd Member Swap: Pinion Preload Problems (1 Viewer)

Joined
Aug 17, 2010
Messages
779
In Real Time:

Swapping FJ60 3rds into my '40. Both 3rds appear to be in good condition, but pinion preload on the rear 3rd (which I will install in my front axle), was WAY high--hard to turn by hand. I had to back the lock nut off about 1/4-1/2 turn to get the preload right. If I torque the nut down to spec, the preload is so high I can't turn it without serious effort.

What's going on?

BTW: I'm reading the Toyota 1980 Chassis FSM for the FJ40--but preload is set the same for the FJ60 3rds isn't it?
 
Joined
Aug 17, 2010
Messages
779
your not reading it correctly there is not a set torque value only a range. you torque until you achieve the desired preload.

Yes, FSM says 145-173 ft. lbs. My preload is probably within spec at about 50 ft. lbs.
 
Joined
Aug 17, 2010
Messages
779
also not sure if you are aware of this but anytime the pinion nut is removed the crush sleeve must be replaced for a proper installation.

Do the FJ60 3rds use a crush sleeve? I thought the shims were used instead.

Obviously, I'm new to this.
 
Joined
Aug 17, 2010
Messages
779
Opened it up--it's the early style with the shims and no crush sleeve. Bearings look fine. Gears look fine.

Now, I will need to add shims to decrease preload?
 
Joined
Mar 30, 2011
Messages
5,344
Location
Huntsville AL or Yuma AZ
in theory yes. but what did you change. if it was properly set up it should retain preload if its torqued to the same value it had before. In my experience even with shims the preload will change slightly while torquing the pinion nut.
 
Joined
Aug 17, 2010
Messages
779
what did you change. if it was properly set up it should retain preload if its torqued to the same value it had before. In my experience even with shims the preload will change slightly while torquing the pinion nut.

I didn't change anything. The preload was (WAY) high when I bought it. I came here to address the issue before I installed it.

Perhaps it has been damaged, and I'm not seeing it, or perhaps the PO took it apart and lost a shim or two. I just need to address the issue and get my truck back on the road.

Thanks for the quick replies. :cheers:
 

ACC Toyota

Supporting Vendor
Joined
Nov 2, 2009
Messages
371
Location
Atlanta GA
As far as i know the 3.70s in the FJ60s never came with the shimmed pinions. If it has a non crush sleeve pinion it is likely a 4.10 not a 3.70
 
Joined
Mar 30, 2011
Messages
5,344
Location
Huntsville AL or Yuma AZ
so your saying it has been apart before? if thats the case then yes it may need more shims. The preload will not change with normal wear if anything it will loosen not tighten. if it was too tight than its possible one or both of the pinion bearings may be damaged.
 
Joined
Jul 20, 2004
Messages
24,774
Location
Chandler, AZ
...
Perhaps it has been damaged, and I'm not seeing it, or perhaps the PO took it apart and lost a shim or two. ...

Have seen them crack/spit shims. If everything else looks good, properly shim it and run it. Especially on the front, they don't see a lot of high speed operation, so :meh:.
 
Joined
Aug 17, 2010
Messages
779
Have seen them crack/spit shims. If everything else looks good, properly shim it and run it. Especially on the front, they don't see a lot of high speed operation, so :meh:.

Thank you Tools R Us and roma042987!

OK, Wow, now I have another hurdle to clear. The bolt pattern on the pinion flange doesn't match my '77 driveshaft. Looks like I can just rotate it 45 degrees and drill to match [what could possibly go wrong with that?!! :doh:] is that what most people do?

Please advise. :)
 
Joined
Jul 20, 2004
Messages
24,774
Location
Chandler, AZ
... The bolt pattern on the pinion flange doesn't match my '77 driveshaft. Looks like I can just rotate it 45 degrees and drill to match [what could possibly go wrong with that?!! :doh:] is that what most people do?

Please advise. :)

That works and is commonly done.
 
Joined
Feb 6, 2002
Messages
15,223
Location
OC, CA
Now, I will need to add shims to decrease preload?

You need a thicker preload "washer". This is the thick shim you will find. You can have 0 to 3 thin shims (.010 thick) which accommodate the different pinion depth shims and there are 25 different size preload washers to select from to get the proper pinion preload. Since you may have problems finding the washer set, you can also add another thin shim and then carefully sand the washer down to get the proper preload. .0005 inch thickness change corresponds to about 2-4 inch pounds of preload, so check often once you get some preload.
 
Joined
Aug 17, 2010
Messages
779
Thank you gentlemen! :cheers:

I just used a driveshaft yoke flange as a guide and drilled the pinion flange out on the drill press. Worked well and that saved me time and money.

I cracked into the 4.11 3rd I removed from the rear of my DD to look for shims. The Pinion nut was not punched, it was torqued on to about 15 ft. lbs., and the oil slinger was in backwards! (I'm beginning to wonder how forgiving these tolerances might be as this work was done by the PO and I've been driving it this way for years.)

The other spacer washer was the same exact thickness but I really lucked out--one more shim and the preload was perfect! I just got the backlash and overall preload right. New pinion seal and in it goes. [HOPEFULLY]
 

Users who are viewing this thread

Top Bottom