i measure the circumfrence of my axle (I think), now what size axle do i need?

[stronglikebull]

I took a string and wrapped it around the inner cv joint and it measures about 12.5 inches. I converted that to mm and it comes up to about 317mm. that can't be the size of my axle. what am i doing wrong? i'm trying to figure out what size axle i need to buy for the driver's side. my transmission isn't the original one and i have no way to know exactly what year it is. It's a TJ model and an automatic 010. I need help with the measurements.

edit: here's the answer to my question.
http://forums.vwvortex.com/showthrea...-tj&p=74298893

[briano1234]

A bit over 11 inches are 90mm, and 12.5 inches are the 100mm.

Now here is another trick, most auto parts stores won't list the axles as 100, and 90mm. They list the diameters in inches. 3.5 are 90mm and 4.0 are 100mm

Your original TJ differential came with 90mm cups so they have been changed..

The easiest way I found is to look at the bolt pattern, if all the bolt holes are equidastant, then 90.
If the bolt holes are off set, then 100.

I had 100mm axles and 90mm cups on my TJ tranny. So I swapped the axles out to have a spare set of 100mm axles, and picked up 2 new 90mm ones.

You can swap the cups out easily enough, and I had to throw a TNA differential back on the car when the axle broke and beat the hell out of my differential till it gave up. So I swapped the axle cups again... no biggie.

[stronglikebull]

A bit over 11 inches are 90mm, and 12.5 inches are the 100mm.

Now here is another trick, most auto parts stores won't list the axles as 100, and 90mm. They list the diameters in inches. 3.5 are 90mm and 4.0 are 100mm

Your original TJ differential came with 90mm cups so they have been changed..

The easiest way I found is to look at the bolt pattern, if all the bolt holes are equidastant, then 90.
If the bolt holes are off set, then 100.

I had 100mm axles and 90mm cups on my TJ tranny. So I swapped the axles out to have a spare set of 100mm axles, and picked up 2 new 90mm ones.

You can swap the cups out easily enough, and I had to throw a TNA differential back on the car when the axle broke and beat the hell out of my differential till it gave up. So I swapped the axle cups again... no biggie.

all good info for my bookmarks. thanks so much. i ordered one from pepboys for 48 bucks. it has a lifetime warranty. the name is fenco. i'm sure it sucks, but we'll see...

[native-texan_in_tn]

Just discovered you were trying to convert the measurements... {chuckle} You definitely didn't want me to answer, considering the way my gpa plunged after my math/calc classes at Embry-Riddle... {cough, hack} No danger of me engineering the next modern marvel, much less a new-and-improved Cabby (if I do, stay far, far away from it...)...

Glad Brian could save the day here...

[stronglikebull]

Just discovered you were trying to convert the measurements... {chuckle} You definitely didn't want me to answer, considering the way my gpa plunged after my math/calc classes at Embry-Riddle... {cough, hack} No danger of me engineering the next modern marvel, much less a new-and-improved Cabby (if I do, stay far, far away from it...)...

Glad Brian could save the day here...

lol, i'm in the same boat with you. it took me 5 semesters to pass 2 algebra courses in college.

[native-texan_in_tn]

lol, i'm in the same boat with you. it took me 5 semesters to pass 2 algebra courses in college.

{chuckle} Yep, trying to replace perfectly good numbers with letters... sheesh... What's the matter with 'em, eh? Thankfully, I survived without having to take any over but I wondered until the very end...

[briano1234]

My issue was I thought I had enough of Algebra.....Then I started in Electronics.... Oy, Vey.......
And back in da day, it was log tables and Slide rules.......

[native-texan_in_tn]

My issue was I thought I had enough of Algebra.....Then I started in Electronics.... Oy, Vey.......
And back in da day, it was log tables and Slide rules.......

{chuckle} Reminds me of the E6B flight-planning computer that most ground-school/flight instructors train with in lieu of the electronic calculator-style versions now available (handy to know should one lose battery power enroute, though!)... When asked why a non-engineering degree required calc and such, our instructor (a guy that had begun his career at NASA working with room-sized Cray computers, punch cards, etc.) just smiled and said, "Because..." I don't think it was the first time he had seen the deer-in-the-headlight looks...

[rabbitnothopper]

i guess if you got 317mm as the circumference then you'd divde by pi 3.14 and get roughly 100mm for the diameter......