Viscous Check?

[MyBlack94GST]

My car was run with different size wheels front to back (1990 AWD) for a while by the previous owner. Exhibits all the signs of a toasted center diff.

I'm going to re-do the center diff guts with the Mitsu kit.

How can I tell if the VCU is ok to re-use?

Thanks,
Mahesh

 

[tstkl]

well from my understanding of vc, they use friction plates that expand when heated (aka tires rotate at different speeds and the friction plates move at different speeds and heat up each other and expand to cause the tires to lock together.) so its kinda like a clutch. if the disks look like they are all in one peice, and there is a good amout of friction material on the disks, it should be ok. if something can be used again tends to be a subjective thing, since a brand new one will almost always out perform a reused part. its really a question of how much do you want this to perform? personally, If I was going in there, I would replace as many wear and tear items as I could.

 

[jtmcinder]

Please, I beg you, stop guessing. Half of what you wrote about the workings of a VC is total nonsense. The fluid expands; not the plates.

To test the center VC (still on the car and assuming an open front diff), lift one front wheel and then, with the car out of gear, try to turn the lifted wheel.

- Jtoby

 

[MyBlack94GST]

Then what? haha... should the wheel be able to turn? What about this test will let me know if the VCU is good or bad?

Thanks!

EDIT: And, is there a procedure for checking it off the vehicle?

 

[Ryan95tsiAWD]

also...a bad VC will show symtoms like a bad center diff. IE: chirping rear tires in sharp turns.

I replaced the inards and eventually the entire center diff and still had problems, when I replaced the VC everything went away. (except the hole in the tranny but that is another story )

 

[tstkl]

Please, I beg you, stop guessing. Half of what you wrote about the workings of a VC is total nonsense. The fluid expands; not the plates.

To test the center VC (still on the car and assuming an open front diff), lift one front wheel and then, with the car out of gear, try to turn the lifted wheel.

- Jtoby

that wasn't a guess, I was positive that was how they worked... I was just wrong, no guessing here, just pure ignorance