HELP! Differential flange swap - how do you do it?

[RPS13]

So I had the dreaded excess pinion play that afflicts many of our trucks. I could only source a good condition used 4WD differential, and from reading the FSM, it didn't seem hard to swap the flanges. In fact, they come off super easy with a 3 jaw puller.

I've got the diff out of the truck, and the flange off, and I CANNOT GET THE DAMN FLANGE BACK ON THE GOOD DIFF!!!

I've got a 12 ton press, and it's basically bottomed out, but now there is in/out play on the flange. The FSM is pretty worthless on any steps here from what I'm finding. Unless I'm just missing a key section???

Anybody got any guidance here? Do I need to take the actual diff itself out and then support the pinion while I press the flange on? That seems like a huge PITA, but I need to get the damn thing back on the road.


I somewhat assumed Toyota's FSM was up to the level of Nissan's, but it seems like they leave out some pretty huge steps.

 

[RPS13]

So I've gone slightly above the 159 ft-lbs it says to tighten the pinion nut, but that didn't get even close to seating it. In fact, both pinion flanges took quite a bit of pulling to pull off.

What's really pissing me off is I think the 4WD and 2WD flanges are basically "the same" except for bolt pattern and height, but the 2WD one has a vibration absorber on it. I never thought it would be anywhere near this hard to swap the flanges, in fact I've done it on Nissan and BMW diffs plenty of times. This is 1000x harder.


What I'm fearing looking at things is I compressed the pinion spacer crush sleeve trying to press the flange on there. Plus I think I might have unseated the bearing on the pinion?



Really irritated at this point, as I thought this would be a fairly straight forward swap, and the factory SST for the job just looks like a basic threaded puller, so I don't see what I'm missing here.


Anybody?

 

[RPS13]

So I got the 4WD flange on the "bad" diff. It went on super easy. I'm even more confused as to why the 2WD flange was such a PITA to get on (and now it seems won't get off). I kept thinking something was up with it so I took it off and reseated it 4-5 times and checked the tooth engagement both times.

So... it looks like the installed height is roughly the same between the 4WD and 2WD flanges (to within 1/16" since one is floating by that amount). I'm thinking of picking up some nuts and bolts and tossing the old noisy diff in the truck and then contemplating what the next step is. I'm thoroughly sick of this, and a little confused as to WTF is really happening with the 2WD flange that came off fairly easily.

Anybody have any advice here, as I'm about at my wits end and thinking I maybe messed up the pinion spacer on the "good" diff.

 

[NoWayOut]

TRy posting this over on 120. You will probably get some help over there.



.

 

[superman3043]

Holy crap dude, I just saw your post over on 120. Didn't realize you were having an issue. I was curious as to how the swap went for you. Have you tried to put the 4wd flange back on the good diff to see how it fits on there comparatively? Is match drilling the 4WD flange feasible? Hope you can get it squared away. I'll try to help however I can.

 

[nevada]

Anybody have any advice here, as I'm about at my wits end and thinking I maybe messed up the pinion spacer on the "good" diff.

if there is still in/out play, you haven't even TOUCHED the spacer yet, so no worries there.

what are you using to tighten the nut?

 

[RPS13]

if there is still in/out play, you haven't even TOUCHED the spacer yet, so no worries there.

what are you using to tighten the nut?

I'm worried when I pressed the flange on I compressed the spacer. I'm just not sure now why there is in-out play on the pinion other than the flange obviously isn't seated all the way down.

I used a piece of 1/8" x 2" steel that's about 2' long and drilled a hole in it, then wedged it under another bolt/stud with a washer and then a torque wrench. Looks a lot like the SST and didn't cost the ridiculous price all those things are. I am definitely getting to 158 ft-lbs, but the flange is not going down all the way (the 2WD one).

I put the old diff back in with the like 5x more backlash than FSM max with the 4WD flange (that went right on with a few taps on a drift) and some M10 nuts and bolts. It's its same old noisy self, maybe a little louder since the only difference between the flanges is the 2WD one has a dynamic vibration absorber ring on it (rubber/steel to counteract the natural frequency of the system).

I'm going to toss a pint of SPT in the diff to see if it tones down the annoyance factor while I deal with the other diff.

I'll probably build a little setup to try to press the 2WD flange off. I still don't know why it bound up so badly. I might just get a solid pinion spacer and set it up to have a little more piece of mind, but I'd rather spend time on my fast car rather than my 4Runner really.

 

[RPS13]

BTW - for anybody pulling this up on a search, you can use EITHER flange interchangeably as far as I can tell, the 2WD just has studs while the 4WD uses bolts. The 2WD one has a dynamic vibration absorber, 4WD is a solid flange.

In hindsight I should have just tossed the good 4WD diff on there with the flange it had. Switching flanges was the only real PITA part of the process. That and realizing just how far you had to pull out the axles (first time getting into a solid axle for myself).

 

[superman3043]

So you got it squared away? I was wondering what you were meaning by using nuts & bolts, since that is what mine uses. Now it makes sense.

 

[RPS13]

So you got it squared away? I was wondering what you were meaning by using nuts & bolts, since that is what mine uses. Now it makes sense.

Unfortunately no, my 2WD flange was stubborn as all hell getting on the good diff you gave me. Soooo... I wasted a whole weekend to swap on the 4WD flange on the old noisy diff and put it back in the truck just to get around.


I was really pissed when it was all going on, but I think I've calmed down enough to where I just want to take the good diff apart, and reshim the pinion with a solid spacer to not worry about it, then put it in with probably the 4WD flange if I can't figure out why my 2WD flange is binding up on the splines.

I was getting very emotional there for a bit with thoughts of trading the truck in and things like that, as I got a Toyota for mechanical reliability and well... it's not been... reggers:

 

[nevada]

Unfortunately no, my 2WD flange was stubborn as all hell getting on the good diff you gave me. Soooo... I wasted a whole weekend to swap on the 4WD flange on the old noisy diff and put it back in the truck just to get around.


I was really pissed when it was all going on, but I think I've calmed down enough to where I just want to take the good diff apart, and reshim the pinion with a solid spacer to not worry about it, then put it in with probably the 4WD flange if I can't figure out why my 2WD flange is binding up on the splines.

I was getting very emotional there for a bit with thoughts of trading the truck in and things like that, as I got a Toyota for mechanical reliability and well... it's not been... reggers:

I just had a thought,

is the depth different on the 2 yokes? im thinking maybe the nut is bottoming out on the spline, and keeping it from pushing the yoke down further.

on that same note...are you using the washer? perhaps the washer is stuck on the 4x4 yoke, and wasn't being transferred over to the 2wd yoke. this would have the same affect, the nut would hit the splines, and never allow the yoke to seat down correctly/fully.

that washer HAS to be there.

 

[superman3043]

Unfortunately no, my 2WD flange was stubborn as all hell getting on the good diff you gave me. Soooo... I wasted a whole weekend to swap on the 4WD flange on the old noisy diff and put it back in the truck just to get around.


I was really pissed when it was all going on, but I think I've calmed down enough to where I just want to take the good diff apart, and reshim the pinion with a solid spacer to not worry about it, then put it in with probably the 4WD flange if I can't figure out why my 2WD flange is binding up on the splines.

I was getting very emotional there for a bit with thoughts of trading the truck in and things like that, as I got a Toyota for mechanical reliability and well... it's not been... reggers:

Man I'll tell you... I love this truck more than any other vehicle I've owned and I'll probably never love another one more... But even I have had that thought on like at least 3 separate occasions when I've gotten frustrated with it. I tend to overreact out of frustration sometimes. But once I've either been talked down off the ledge or given myself enough time to calm down and just fix the problem, I've always been thankful that I decided to keep it. Good luck man.

 

[RPS13]

I just had a thought,

is the depth different on the 2 yokes? im thinking maybe the nut is bottoming out on the spline, and keeping it from pushing the yoke down further.

on that same note...are you using the washer? perhaps the washer is stuck on the 4x4 yoke, and wasn't being transferred over to the 2wd yoke. this would have the same affect, the nut would hit the splines, and never allow the yoke to seat down correctly/fully.

that washer HAS to be there.

Flange spline height is the same between the flanges. The P/N for the 4WD and 2WD diff carriers is the same, and the pinions are the same.


There was way too much resistance to pull the 2WD flange down with just the nut. I hit 158 ft-lbs and it was barely down the splines. I figured it was just slightly bound up so I scotchbrited the entrance to the pinion splines to knock down any burrs (didn't feel any), and pressed it on. Didn't take much pressure from the press, but then it stopped and there's play.

There was no washer under the pinion nut on either diff, so I'm not sure what you're talking about. The nut has a flange, and the FSM says to coat everything in hypoid gear oil.

I'm sure I'll get it fixed somehow, and it's not that big of a deal now that I know how to pull everything apart quickly. The brakes even gravity bled really quickly, so that was easy. I just don't really enjoy working on my daily driver anymore, which is why I no longer own any BMWs.


Anybody have any links to vendors that sell the whole pinion spacer kit? I keep getting hits to a bunch of general driveline shops that reference 4 cyl T100s and stuff, but I want to know for sure it'll work. I seem to also recall a place that'd rebuild your Toyota diff for you. Maybe I could find someone local to do it, because again, I'm getting sick of working on the daily at this point. Then again, I've seen quite a few driveline shops screw up setting up a diff.

 

[ebg18t]

Might be worth calling (ECGS) East Coast Gear Supply over in Raleigh NC.

 

[superman3043]

Yeah I don't remember there being a washer with the pinion nut either.

Hit up Chase Perry at East Coast Gear Supply. He knows these diffs in and out and should be able to answer any questions that you might have. I bought my solid pinion spacer set up through them, but if I remember correctly it came in a Trail Gear package, so they probably just re-sell a TG part.