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Mon Oct 02, 2023 7:36 pm

I recently read that CV axle flange bolts should be tightened or loosened only when the wheels are on the ground. What would the result be if you do this while the car is on a lift?? Anybody have any thoughts?

Of course I read this after I installed my axles.

Thanks, John.

Mon Oct 02, 2023 9:05 pm

I`ve never had a problem doing mine while it's in the air, or just tightening them without a torque wrench.

Tue Oct 03, 2023 8:30 pm

I see no mechanical harm in tightening them while the rig is jacked up, that said I usually just have mine up on ramps and will jack the suspension up with a bottle jack as needed so that I can rotate the axle for better access to any given bolt, but the weight is on the tires when I do the tightening for safety reasons.

This is one of the few places I routinely use a torque wrench and couple that with the Vanagon torque spec of 33 ft*lbs.

.

Wed Oct 04, 2023 10:09 am

Wildthings,

You bring up an interesting point regarding torque specs. I think like the factory manual states it should be 25 pounds but I’ll double check. I double checked the tightness several weeks ago and some were loose. Maybe 33 is a better torque number.

John

Wed Oct 04, 2023 10:38 am

Johnnyw wrote: Wildthings,

You bring up an interesting point regarding torque specs. I think like the factory manual states it should be 25 pounds but I’ll double check. I double checked the tightness several weeks ago and some were loose. Maybe 33 is a better torque number.

John

T-2 Transporters have some problem with the bolts coming lose and sometimes even breaking, the heavier Vanagon has a much lesser problem with the bolts with the only real difference between the CVs on the two vehicles being the tightening torque. It is common to find that the outer race of the CVs have shifted a bit relative to the flanges putting the bolts in shear when they are designed primarily to be under tension, the higher torque seems prevent this.

FWIW, when I buy a new to me VW that is far from home and go to pick it up, one of the maintenance things I do is tighten the CV bolts before hitting the road home, the bolts are seldom even up to the 24 ft*lb spec and often pretty close to falling out.

Wed Oct 04, 2023 7:00 pm

Wildthings,

Thanks for the information. In the next few days I’ll go in and re-torque all of my bolts. Probably replace the washers at the same time.

John.

Sat Oct 07, 2023 12:06 am

Johnnyw wrote: I recently read that CV axle flange bolts should be tightened or loosened only when the wheels are on the ground.
I think that's only a safety warning. Someone thinks the force pulling on your ratchet might dislodge the car from the stands.

Otherwise it's complete bullshit.

Sat Oct 07, 2023 3:15 pm

Bruce,

You may have hit on the reason. I’m gonna go with that thinking for now.

Thanks, John.

Sat Oct 07, 2023 3:58 pm

I always torque my CV bolts with the tires off the ground. That way I can turn the wheel to the next bolt while I'm under the car.

Sun Oct 22, 2023 10:49 am

I also used the updated torque spec of 33 FtLbs. I will say it is best to throw the bolts away if you ever take them off again. They are pretty much a one time use item at that torque. Also, look up NordLock washers. Those washers with 33 FtLbs, and you will not have a cv come loose on you again.

Sun Oct 22, 2023 8:56 pm

Vanapplebomb wrote: I also used the updated torque spec of 33 FtLbs. I will say it is best to throw the bolts away if you ever take them off again. They are pretty much a one time use item at that torque. Also, look up NordLock washers. Those washers with 33 FtLbs, and you will not have a cv come loose on you again.

Vanagon guys reuse their bolts all the time. Since at the higher torque there is less pulsating stress on the bolts they may suffer less fatigue than bolts tightened only to 24 ft*lbs. They are certainly less apt to experience sheer forces, which happens readily at the lower torque.

Wed Oct 25, 2023 2:17 am

Vanapplebomb wrote: .... it is best to throw the bolts away if you ever take them off again. They are pretty much a one time use item at that torque. ...
Even at 33 ftlbs, I wouldn't throw them away. You could be throwing away good German screws and putting on junk China screws.
The bolts on my CVs are all original 50 year old bolts. Never had one break or strip out.