VN_SS_CM
Active Member
Hey guys, I was changing the centre out and buggered up the shims...what is a good backlash currently with my spare shims backlash is 007. It's an old 3.45 VL 28 spline borgwarner....
Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
Borgwarner backlash
- Thread starter VN_SS_CM
- Start date
VN_SS_CM
Active Member
thanks mate I adjusted to 0.005, 0.007 and even 0.012 and when you run the car on the jack stands the diff is making a hissing noise as it spins and the axle is harder to turn by hand then my other diff I have sitting here untouched only difference is I have installed a torque lock lsd....
Grimes
Well-Known Member
- Joined
- May 7, 2020
- Messages
- 410
- Reaction score
- 275
- Points
- 63
- Location
- NSW
- Members Ride
- VS Commodore Series II Ute
Putting in a new torque lock centre will feel harder to turn compared to a worn open centre but without being there to hear the hissing sound it's hard to tell if it's an issue or not.
If you've changed to a new torque lock centre then you should've had to check the gear mesh pattern, carrier pre-loads, pinion preloads and backlash. If you have and they're all OK then it may not be an issue at all. The other issue which is less likely is the pinion gear being in light contact with the centre housing due to the housing being larger in diameter where the pinion is closest. Now that you've run it, it will be easy the spot because the centre housing will have scour marks around the circumference where the pinion teeth are rubbing against it.
I recently overhauled and converted an M75 and had to skim the pinion head to maintain a thermal clearance allowance. It was close enough that a +0.2mm shim put it into contact. Another M78 Ford diff I helped with needed 1.0mm taken off to achieve clearance, but the M78 pinion bearing seats are shallower than the M75's.
If you've changed to a new torque lock centre then you should've had to check the gear mesh pattern, carrier pre-loads, pinion preloads and backlash. If you have and they're all OK then it may not be an issue at all. The other issue which is less likely is the pinion gear being in light contact with the centre housing due to the housing being larger in diameter where the pinion is closest. Now that you've run it, it will be easy the spot because the centre housing will have scour marks around the circumference where the pinion teeth are rubbing against it.
I recently overhauled and converted an M75 and had to skim the pinion head to maintain a thermal clearance allowance. It was close enough that a +0.2mm shim put it into contact. Another M78 Ford diff I helped with needed 1.0mm taken off to achieve clearance, but the M78 pinion bearing seats are shallower than the M75's.
Last edited:
VN_SS_CM
Active Member
I ended up shortening another housing and measured the torque lock centre to ensure it was identical in size to the open centre...I also took back lash measurements prior to pulling it apart and its exactly the same as when the old open centre was in. Yeah I had to 'machine' the pinion down to clear the housing. With my other noisy housing I reinstalled its matching open centre and the hissing noise is still present seems like the pinion bearing is worn.....this will do for now thanks for your advise.