T90 question

Well back to my original problem of the horrible noise from my t-case / trans. turns out i goofed up the mainshaft quite a bit because i dropped some roller bearings but anyhow, it's going to be cheaper to buy the long mainshaft for a t90 / d18 setup (because i have a spare t90/d18 lying around). Will swapping my t14 for the t90 affect my acceleration / top speed, etc?

 

hmm Mike, I came up with diff ratios than you:

T90- 3.33, 1.55, 1.00, and 3.79 for reverse

T-14- 3.10, 1.61, 1.00, and 3.10 for reverse

the only real benefit switching to T14 would be the synchro 1st gear
also, if you have Warn OD with the T90, it won't work with the T14
diff spline count

 

there also was an early T90 wagon/pickup trans that had lower first gear/cluster ratio, but they are a little hard to find. The end result is a lower first gear ratio only IIRC.

lovemyjeep: T90 parts are plentiful, maybe repair what you have.

 

t-90 first gear numbers were right (in both posts)

Somewhere along the line the first gear ratio changed slightly. If the transmission has not been fooled around with the 3.3 ratio will be indicated by a threaded shift rod (for the knob). The older 2.98 ratio did not have a threaded rod......

 

You can also get a t-90 from an early scout that is the lower first. Just have to change to the jeep input shaft. Also should have an 18 without the rear brake assembly.

 

This is off of Novaks sight:

The T90A has:
1st 2.98
2nd 1.66
3rd 1.00

The T90C has:
1st 3.44
2nd 1.85
3rd 1.00

 

thanks Kamel and Mike !
knew that info was floating around out there somewhere