Okay, I'm wondering here... how many of you guys that have swapped Ap1>Ap2 diff's or vice-versa, and have had to do the flange swap? Basically, this applies to everyone who has removed even just your stock diff flange, or swapped them for another model year one.... WITHOUT rebuilding the diff internals or replacing the inner spacing collar-crush washer.

Any problems anyone has run into after the swap!!?? Like, how many miles does everyone have so far on their swapped flanged-differentials or how long have you had your in for?? I'm just trying to see the success/failure rate of people having them done... lmao.

Only curious!

Thanks guys!


I already know the whole schpeal on everything.. I know the torque specs for the new pinion lock-nut.. blah, blah... just wondering how successful everyones have been!?

Thanks!
-Tylor

 

The flanges interchange just fine, they pop in and pop out like axles on a FWD car.

I had an ap2 diff with ap1 flanges in my ap1 with no problems at all.

 

Maybe I didn't clarify myself.. haha, I'm talking about the ONE front flange on your differential. Also called an output flange, companion flange, or a mating flange...

The reason why I ask, is because it requires a VERY specific torquing of that 22mm center nut inside the flange, only if you do the swap WITHOUT replacing the pinion distance collar (big crush washer basically) inside the differential. Also you must replace that locking nut when the flanges are swapped, because if you re-use that, the torque spec of that nut will then be innaccurate. The reason the torque of that center pinion lock nut outside of the flange is crucial, is because generally, when the flange is swapped, it is recommended to replace that pinion distance collar inside your diff. When your diff is first assembled, or has been rebuilt, it uses a new pinion distance collar (that crush-like washer), and when the flange is tightened onto your pinion outside of the diff, that distance collar is crushed to a tolerance of 90-200ish ft-lbs.

Basically, when swapping that output flange, which attaches to your main driveshaft, it is usually necessary to rebuild your differential, because of that inner crush-washer, distance collar, having to be replaced. So, instead of going through the whole process of tearing your differential apart to just replace that... we are supposed to "mickey-mouse" the flange swap, by torquing it down to that minimum tolerance of 90-95ft-lbs of torque on that flange nut, which presses onto the crush collar inside, which in turn, if torqued down incorrectly, will press your pinion against your main ring inside your diff, damaging you assembly.


Soooooo.. with that said, anyone that has done the swap of that output flange on your diff.. I'm trying to see how long you all have been riding on that newly swapped older/newer-gen differential with that replaced flange... Basically, trying to figure out the longevity everyone is seeing after having done the flange change, and exactly HOW well everyone's setup is holding up after having performed this specific torquing of that pinion nut for the flange...

Only curious, because I'm about to have my AP2 flange swapped over onto my geared 4.77 AP1 diff on Monday! Just wanting to see the reliability of everyone's, or if there have been any following concerns with anyone's swap!

Thanks! let me know guys!!!!

ps, PEANUTBUTTER, is this the ONE flange on your differential that was swapped????? if so, how many miles or how long have you had this on your S for? Thanks!

-Tylor

 

Bump for help!!!!

 

94 pounds of torque is minimum

 

Yea, that's precisely what you had said on the phone yesterday Ben!!! thanks again man.. I REALLY appreciate your help and patience with my n00b-ass on the phone also... I have done everything to my cars before myself... MINUS anything relating to my differential.. LOL.. so this is sort of a new-world to me..

I am only asking folks on here, like how long has it been since they have replaced their flange or messed with it any... just trying to gauge for myself, the success/failure rate of everyone's own-effort of torquing down the pinion nut... without replacing the crush collar inside..

I REALLY hate having to 'jimmy rig' things without properly replacing the crush collar you know...? so, hahaha.. ya.. i'm just sort of trying to make myself feel a little more comfortable about doing this..

Thanks again Ben!!!!! when I come down to Florida in the summer, I'll have to come and visit.. maybe you can show me around to some local meets!??

 

You need to measure the pinion turning force before removing the flange. Get a inch pound beam style wrench.

Then swap flanges and slowly retorque the pinion nut until the same turning force is reached.

 

^I read your exact post somewhere in another thread stating that almost precisely... and I actually read it off word for word to Ben when I was on the phone with him yesterday...

when you say turning force, you mean, the loosening turning force once its tightened down?????

for instance, when I'm removing the nut for the first time and it reads like 8inch-lbs... then when i re-install the new flange and re-torque down the new pinion nut, i torque it to that 8inch-lbs again???

Ben had mentioned that I torque it down to like 80ft-lbs, feel it accordingly to how it spun prior to the swap, then continue torquing up to about 94-95ft-lbs until that spinning-feel is reached.. he said it should take no more than about 95ft-lbs to reach the desired spec. and also to thoroughly clean the threads and loctite the nut onto the pinion... I have the blue and red loctite, which would be more appropriate to use for this application? blue is temp, red is semi-permanent... Sorry, but to be honest, I have never used an inch-lbs torque wrench... lmao, I've used a regular ft-lbs like a million times, but sort of unfamiliar with how you want me to measure the turning force..??? Rrrrr, i'm retarded. lol

Please advise.. thank you to you both....

slows2k, what is your name? you've helped me before also... thanks!!!!
-Tylor

 

If you get a reading of 8 inch pounds first you can torque down a little more after you put the new one on till 10 or 12 inch pounds. 12 inch pounds is max and will assure you have got enough preload on the bearing.
Lock tight blue and a new nut is good to use.

 

when using the inch-pounds torque wrench.. and when i first measure the pinion nut before swapping the flange, and after swapping the flange... how do I measure the nut with the inch-pounds wrench???? the removing force of the nut?? sorry, but its late, and i'm a little retarded.

or when i first measure it prior to the swap, do i measure while tightening or loosening??? again, a dumb question... but thanks Ben!!!!!!!!!

-Tylor