05-12-2002, 11:42 AM
Well, I am getting a T-Case made, so I had to do the "pull the t-case and look at the shaft" routine...I counted the splines (23) and measured from the bearing surface to the edge of the gear, and came up with about 7/8". Not sure if this would be considered the "long" input gear or the "short" input gear.
Did I do this right? I sure as heck don't want to do it again...getting the case back in with just a floor jack and jackstands was about like trying to give a grizzly bear a reacharound in the bathroom of a Boeing 737.
05-13-2002, 07:14 PM
For the record, I talked to my T-Case guy today..he told me that I have the short input gear style on my 249.
If you want to avoid the agony of actually dropping the case and having to raise it back up, I think if you very carefully ease the case back, you can see just enough to figure out what gear you have. The short gear is just a little bit longer than the mounting studs, if you can pull the T-Case farther back, you have the long gear.
Don't want to inject confusion but that sounds like the short version. I have three input gears out in the garage. Short 21 spline, short 23 spline, and long 23 spline. Can't measure lengths relative to the case since the bearings are out but I recall short was just under an inch outside while long was ~1.5". Just now, measuring from the bearing-contact surface to the end of the gear:
Long = 2.8"
Short = 2.2"
BTW, I'm not a big guy but found it simpler to hoist these cases up by hand. (249 & 231's) My first attempt with a jack left lots of fluid on the driveway and had me creating new bad words. It got in the way more than anything. Simplest is with another person to stabilize and guide in the studs.
Correction. I have 3 input gear lengths.
Case/origin/splines/Length from gear end to inner bearing-contact surface/thickness of input bearing.
249/94 zj mated to a 4.0L/23/2.38"/.94"
231/94 yj mated to a 2.5L/21/2.21"/.94"
231/99 tj mated to a 4.0L/23/2.82"/.64"
(The 99 tj gear has a monstrous shoulder that makes up for the thinner bearing.)
I'm confident in the differences. Measurements are rough but consistent, rounded to the nearest 1/100th.
Sorry if I'm clouding the water. Just trying to show these things vary. With different engines and cases over the years there may be a dozen gears running around. More once you get past Jeeps. Back to whether yours is "long" or not, I'm useless. All I can tell for sure is my 94's are significantly shorter than the 99, and .75" sounds right for my 249's external gear measurement from last month.