Slippage while tightening lugnuts - clutch?

[RatLabGuy]

Tonight I was rotating my tires, and had the front end jacked up on both sides.
While tightening the front lugs, I was surprised to find that as I really tightened them down, the tires would actually rotate - it took a lot of force but it would.
I know normally w/ a typical open differential, if both wheels are up off the ground turning one should allow the other to rotate the other direction. But that should be relatively frictionless - and this is a 5spd w/ it in gear.
What allows this slip? Does that indicate the clutch is slipping?
I've been having issues w/ it popping out of gear but I chocked that up to worn synchros or motor mounts (185k miles)...

 

[MrGiggles]

With the wheels off the ground and transmission in gear, it shouldn't take much effort to rotate the wheel. The other will rotate the opposite direction. You should be able to do it easily by hand, if not you have a brake dragging.

A slipping clutch would manifest itself while being driven. The force required to move the car up an incline is much higher than what you can generate with a torque wrench. Popping out of gear is not related to the clutch.

 

[P-Funk!]

RatLab!

Wow ! You have been a member a long time!
I remember when you joined.

 

[RatLabGuy]

yeah, can't quite shake the P5.
Technically this is my 2nd, totalled the first in '09... replaced it immediately w/ an identical one... but I guess I'm coming up on 9 years here.

 

[kamesama980]

Auto or manual doesn't matter. Unless you have a pre-loaded LSD (like clutch type) the wheels should turn opposite of each other pretty easily. This is because you have a differential. In 9 years you've never noticed this?

If you do have a pre-loaded LSD, if the other wheel is spinning opposite, then the LSD is slipping (normal unless you have a super tight racing diff that would really suck on a FWD) or if they're spinning the same direction could be the clutch slipping or you could just be spinning the engine. There's only so much friction.

As mentioned, if you don't have a LSD in the diff and it takes more than a pinky to turn the wheels, you might want to have a look at the brakes.

 

[RatLabGuy]

Yes, I have noted this effect of the wheels turning opposite one another on this and many cars.
However I though if it was turned off while in gear (5spd) the output shaft would still be affixed to the engine flex plate preventing it from moving. But I guess with the open differential it would just spin.
I guess it just caught me funny that it wasn't one way or the other. Yeah maybe a caliper was sticking.

Irrelevant now since the trans forks are fubared and the whole thing has to come out anyway