BEnt Rear Companion Flange? Troubles HJ61 JDM

[2rivers]

I've really done it now - somehow.... Apologize now for long sob story and post...

After months of trying to trouble shoot this - a mechanic finally was able to pinpoint my source of resonantion / vibrations woes on our HJ61 JDM. Truck has mostly been parked during this time. So he watched the truck "driving" on the hoist and noticed that the rear pinion companion flange "wobbles" for lack of better words. I saw it with my own eyes - it wobbles and transfers that wobble (albeit minor) to the entire rear driveshaft. !!! So does the little dust sheild against the diff housing!

The truck resonates quite badly starting at 80 km/hr and gets worse with more speed. Really noticeable when backing off on throttle quickly. Yes tires are fine, rims balanced, wheel bearings OK I think - fronts anyways.

I'm sh!tting my pants for a few reasons - it has the cable lockas in it and I dont know what is compatible with the CDN/US FJ/BJ/HJ version we got particularly with respect to the pinion and crown gears / 3rd member etc.

MOST OF ALL - I am mystifies how this would have happened in the first place! I wheel the rig but last time I went out 4x4 I did a river crossing and I know I did not hit a big assed boulder or anything else. There is not sign of a big hit under there. I cannot for the life of me figure out what happened. I am REALLY scared the pinion input shaft is bent but I figure if I hit something to bend that - the rest of the truck would be in a scrap heap. I tow a heavy trailer every once in awhile but really...this is a cruiser. Has anyone heard of a bent companion flange?????

I did change the pinion oil seal awhile back and after this I think I started to notice the resonation - but it was an easy job and I dont think it is possible to screw anythng up - I did torque the stakenut to spec and all driveline is in phase.

My mechanic advised to get a new/used companion flange for now and try that - which I will I think part # is 41204 - 60050. Would the pinion and input shaft be different between truck with and without the stock cable lockers?

GEez....I still cant believe this.

Any constructive advice would be appreciated!
Thanks
John

 

[2rivers]

YEah - sorry I meant to ask if anyone has an old companion flange lying around to mate with a 60 series rear driveshaft at the rear diff. Let me know what you have. Thanks a bunch.

 

[brownbear]

Johnny, I am home next weekend. I'll come by with my coveralls on and have a look. I have my stock gear set too, as do you in the other trucks, so it should be easy enough to fix. Odd that it would be bent. I can see out of torque or loose, but not bent.

I take it the front tear down showed nothing? Did you re-tighten the wheel bearings and it took out that slop?

No worries we will figure it out....

 

[brownbear]

To elaborate my thinking, I bet you have a frozen or stiff u-joint and like my Bj60 original flanges the bearing is worn out. So the u-joint causes the companion flange to move on rotation. Go underneath and grab the flange and see if it moves up and down or side to side. If it does the bearing is shot and the stiff drive shaft is making it look bent.

It should not be hard to find the timkin bearings for your diff. AT least it isn't your DD right now.

 

[2rivers]

Thanks Brownbear! I Pm'd ya. Defintaley got some cold brews on hand for when you have some time available!