cv joints size

[dyoungen]

I'm going to r&r the cv joints in my 1985 Jetta. I called the auto parts stores and there is 2 different sizes. How can I find out what size my cv joints are without removing them or is that the only way to be sure. They tell me they are 90mm or 100mm.

[theman53]

I just went through this.
If you can crawl under the car and measure the inner where is bolts to the trans that is your best bet. 90mm is about 3.75 inches and 100mm are about 4 inches. That is diameter, so if you can't get the diameter then do circumference and divide by pi....3.1415965.....don't quote me on the actual value of pi. it has been awhile:D
But with that 3.75x3.1415= 11.78 diameter
4x3.1415= 12.56 

That is about 3/4" difference so you should be able to tell without taking anything off.

[fatmobile]

D=2 X pi X r

[Baron VonZeppelin]

You can buy the whole shooting match - axleshaft with both cv's, boots, grease, axle nut - and some come with new bolts, for about same or less than replacing cv's. And its ready to bolt.

CarQuest has remand's for $53
Oreilly has New for $60
AdvanceAuto has New for $70

just putting it out there in case its a better deal for you.

[Baron VonZeppelin]

Diesel trannys use 90mm from factory.
If you still have ACH code tranny - its 90mm.

Never a sin to measure for verification though.
Things can get changed on cars.

[rs899]

I have a $53 reman from Carquest that I am going to put in this weekend. 

1) It's German
2) It has new boots
3) It has an unlimited warranty for when the boots crap out 10 years from now

What could be better? 

You almost can't buy the boots for $53....