Question about Diffs

[Bair]

I have been told and I have read that the 95 4Run had 4.10 or 4.11 rear ends. So I jacked it up, marked the drive shaft and the wheel and did the spin test. I came up with 2.1 or 2.2.

I ran the test several times. I even backed up the wheel and rolled it to the mark to get and slop out of the system.

I still get somewhere between 2.1 and 2.2. Does anyone know the stock read end reduction on a 95 SR5, Limited Edition??

THX

 

[Gryphon]

You are on the right track, but are missing some parts of your equation. To get your axle ratio when it is unknown try this:

(engine rpm X tire diameter) / (mph X 336)
example: 3000 rpms at 65 mph with a 26 inch tire:
(3000X26)/65X336)= 3.57

This is from http://www.chevyhiperformance.com/techarticles/148_0208_gear/index2.html

Here are some other interesting formulas:
http://www.angelfire.com/sd/BSP/formula.html

Hope this helps some.

(dang, wish I knew this stuff back in high school! I could have done better in algebra with an application I could understand!)

 

[beeper]

I don't have the answer to your problem but I think I can give you food for thought...it sounds like the drive shaft has to turn twice then you would have the ratio you expect. I think it has to do with engine revolutions..the camshaft has to turn twice for each revolution of the engine and somehow that relates to drive shaft having to turn twice, something like that.