FJ80 Post knuckle rebuild pull - Edit: problem found (1 Viewer)

[BlutoF15]

The knuckle job is complete, I’ve put about 25 miles on it. Searches here turn up some almost but not quite related threads (along with some gnarly looking stuff failure photos.)

The truck tracked and steered like new before work, and now has a distinct pull to the right. Nothing stood out on reassembly, and nothing super weird like “hey, what’s this part left over” or anything visually incorrect.

Of note, I drove it after completing the left side first because I had to move locations. No pull. Any ideas? Is it just common to have an alignment done after this job?

 

[bhsdriller]

No not common and alignment isn't needed.

Overtightened the nut on the wheel bearings? Or something else sounds like it's dragging
Jack it up in the front and spin each wheel to compare

 

[BlutoF15]

No not common and alignment isn't needed.

Overtightened the nut on the wheel bearings? Or something else sounds like it's dragging
Jack it up in the front and spin each wheel to compare

Will do when I get home.

The right side was actually dead center of the preload range per spring gauge but always a chance I screwed it up after checking. (And this is why I ordered a handful of star washers in addition to my kit.)

Oddly enough, the left side was tighter during reassembly.

 

[Kernal]

Does it actually pull ie: when you step on the brakes, or does it drift to the right, quickly, slowly, abruptly?? Did you replace the brake calipers, pads or flexible brake lines? Any difficulty pushing the pistons back to install the pads?? Checked the tire pressure, equal right to left??

 

[BlutoF15]

Does it actually pull ie: when you step on the brakes, or does it drift to the right, quickly, slowly, abruptly?? Did you replace the brake calipers, pads or flexible brake lines? Any difficulty pushing the pistons back to install the pads?? Checked the tire pressure, equal right to left??

It’s a linear, smooth and persistent pull. No change during braking nor acceleration other than it increases to a certain degree with speed. I’ve driven it on a four lane just to make sure I wasn’t being overly sensitive to crown in the road.

New caliper bolts but nothing else in the brakes this go around. No issues during reassembly. I will say the brakes are good but seem a bit softer (pedal feel) than before. Could be differential drag there? Good idea.

Tires are effectively brand new but another good check. I’ll take a look.

 

[robnicko]

Did you remove the trunnion bearing shims during the job and if so did you make sure to put them back in their original upper & lower positions?

 

[BILT4ME]

Will do when I get home.

The right side was actually dead center of the preload range per spring gauge but always a chance I screwed it up after checking. (And this is why I ordered a handful of star washers in addition to my kit.)

Oddly enough, the left side was tighter during reassembly.

I'll bet your wheel bearings were not seated and now that you've put on a few miles with the truck on it, the bearings have moved and now your wheel bearings are loose. This will cause a misalignment and a brake drag to the affecting side.

The fact that you used the fish scale tells me you followed the FSM which has been proven incorrect.

Tighten the inner nut to 35 LB-FT while rotating, then lock washer, then outer nut at 45 LB-FT, then fold over tabs, one on inner nut, one on outer nut.

 

[BlutoF15]

Trunnion shims removed, cleaned, replaced. All good.

Copy all on the bearings being seated. Just got extended for 3 days on a work trip but I think I’ll start with rechecking preload and re-bleeding the brakes.

As always, super glad there are smarter people in the world than I am. Thanks!

 

[nukegoat]

I'll bet your wheel bearings were not seated and now that you've put on a few miles with the truck on it, the bearings have moved and now your wheel bearings are loose. This will cause a misalignment and a brake drag to the affecting side.

The fact that you used the fish scale tells me you followed the FSM which has been proven incorrect.

Tighten the inner nut to 35 LB-FT while rotating, then lock washer, then outer nut at 45 LB-FT, then fold over tabs, one on inner nut, one on outer nut.

Loose wheel bearings won't create brake drag typically

 

[BILT4ME]

Loose wheel bearings won't create brake drag typically

REALLY loose ones will.

Either way, loose wheel bearings can create a pull to that side due to misalignment, brake or bearing drag.

 

[nukegoat]

REALLY loose ones will.

Either way, loose wheel bearings can create a pull to that side due to misalignment, brake or bearing drag.

Yeah the loose brake pedal sort of substantiates it

 

[BlutoF15]

Not sure how I missed the second part of your post @BILT4ME but I’ll double check those for sure. And keep checking, at least until I run out of spare washers.

 

[BlutoF15]

Welp. This has gone to full on sht show.

Removed the flange, somehow the brand new cone washers were near impossible to remove, the 30 year old ones were a breeze. (Yes, OEM.) I removed the inner and outer lock nuts and washer, retightened to not FSM spec.

Now I can’t reassemble it. It did seem to turn maybe a bit smoother, but on my originally reassembly I had a whale of a time getting the inner axle to pull out far enough to install the c clip. This time? Zero movement. I’ve put enough pressure on this washer to start bending it, this is all I have.

And I’ve now used my last spare flange gasket.

I recommend again to anyone considering this, just don’t. Take it to a shop, pay what they ask, enjoy your cruiser. I’d rather put a timing belt in a Honda while hanging Sheetrock on breaks than do this again.

Any ideas how to fix this so I can get it to a shop? (If I can find one?)

 

[BlutoF15]

Managed to get the flange off without damaging the gasket. Still almost couldn’t get it back but managed to wiggle alignment enough when reinstalling that I got it to clear. C clip is on, it’s back together.

No change to the pull to the right. Brakes have been bled so many times I’ve lost count. It’s going to the shop and if that doesn’t work, to the bottom of the Gulf of Mexico.

 

[SpenserAK]

What all are you doing to seat the wheel bearings during assembly?

 

[BlutoF15]

Everything exactly per these two. And discrepancy I went with OTRAMM.





Went and drove a few miles at highway speeds. There actually is an improvement in the pull. Close enough for me. Still have completely bone dry knuckles and the brakes aren’t perfect, but it’ll have to do. I’m beyond done with it. I’ll see if a shop finds anything.

 

[SpenserAK]

Both could go a little more in depth on that part, but still very good videos that I’ve watched more than once.

I used this as an additional step for mine



^ in conjunction with what @BILT4ME said above (and discussed in below screenshot), as well as the discussion here. Sort of made a mashup of everything that made sense. Finished my rebuild yesterday and probably spent more time ensuring seating the bearings than necessary, but it worked out well. I did the initial 43lb & spin a bunch both ways, repeat until 43 keeps holding.. then my final number seemed to be 25lb for the right feel. We will see if anything changes after a bit, but I feel good about it.

 

[BILT4ME]

Both of them could go more in depth on preload & properly seating bearings, but still very good videos that I’ve watched more than once.

I used this as an additional step for mine



^ in conjunction with what @BILT4ME said above (and discussed in below screenshot), as well as the discussion here. Sort of made a mashup of everything that made sense. Finished my rebuild yesterday and probably spent more time ensuring seating the bearings than necessary, but it worked out well. I did the initial 43lb & spin a bunch both ways, repeat until 43 keeps holding.. then my final number seemed to be 25lb for the right feel. We will see if anything changes after a bit, but I feel good about it.

View attachment 3131116

As an FYI, I have now settled on 35 LB-FT for the inner nut and 45 LB-FT for the outer. I have had zero problems since I've gone to that level.

I also changed my double nuts to Trail Gear nuts. My jury is still out on those. I like the thicker nut, but they tiny little Allen head screws are a PITA to get tight and undo again when I need to. They are almost a single use screw. Also, alignment on the screws to the TG nut is less than stellar. As in, one screw will install and work with the tang on it, but the second screw is near impossible to get hooked without cross-threading.

 

[ZetheGSD]

Weird question and I’m sure that you didn’t do this, but by chance did you twist a brake line when installing the caliper? I’ve seen calipers hood residual pressure from brake lines being looped one too many times.

 

[SpenserAK]

@BILT4ME good to know, thanks. If I find it to be a bit too loose down the road, I’ll snug ‘em up.