What to exspect..

[Jump This]

I had someone ask me an interesting question the other day....He wanted to know what to exspect when he drops his R&P ratios. That is to say...if he used the 4:56 would his final drive be close to his 3rd gear now (automatic on an 95') And what about if he changed to the 4:10? I couldn't help..maybe someone here?
And before you ask what size tires he has.....as I see it...its irrelevant....(not the drivability, the final ratio)

 

[Georgia Mike]

IIRC,someone on here did the math and figured out that 4.88's were the same in overdrive as 3.55's were if you left it only in drive. Probably not what you were looking for,but it's a start.

 

[Jump This]

Close enough!
Thanxs...

 

[Jump This]

expect....that is

 

[Eagle]

Look t at the thread on the AW-4 overdrive ratio and you'll see that the year of the XJ is a factor, because the OD ratio changed.

We're talking about an AW-4, so third gear is direct (1:1 ratio) drive. Final drive ratio for that is the axle ratio ==> 3.55.

The OD ratio for a '95 is 0.75:1, so the final drive ratio will be the axle ratio multiplied by the tranny ratio.

4.10 x 0.75 = 3.075

4.56 x 0.75 = 3.42

4.88 x 0.75 = 3.66

 

[Jump This]

So....I tell him to drive around in third all the time and that would give him an idea of what he would get with the 4.56....and if he wants a lower RPM at any given speed...go with the 4:10.
Okay...so that is kinda close....but he would get the picture (heck.....and now I get it too!)

 

[Eagle]

Actually, driving around in 3rd gear he'll be right beyween where he'd be with 4.10s or 4.56s. Once he gets a feel for what it's like in 3rd, he can decide if he wants just a bit more gear, or just a bit less.