1996 Chevy Tahoe. I buoght the Tahoe and in a month the transmission case cracked in the rear in front of the spacer to the transfer case. I bought another transmission case and rebuilt it. I drove the Tahoe less than twenty miles and it cracked in the same place. What could be causing the transmission case to crack? Thanx for any ideas!
Take 'em off and move them up
Severe vibrations from mabe a out of balance or bent drive-shaft .I have seen this problem before ,but it was always because of a previous installer that did not get the 4 bolts tight enough that hold the adapter to trans.
well there are two areas that your going to have to look at 1 being drive line angle the 2nd being the mount system. meaning motor mounts and transmount somewhere you are getting flex in the system and its binding up or getting way out of shape. there is the slim chance as well that there is a difference in gear ratio between the front and rear differentials since it is 4wd. not knowing anything about the previous owners there is always the chance that they blew a diff. and just replaced it with another of the wrong ratio first start with drive line angle's and mounts before looking into different ratio's good luck to ya.
I own a transmission shop, and have seen this before. If you will check with Chevrolet, they will tell you that its the braces that run from the transmission to the engine have been removed. They are a real pain in the neck to get in and out, and I'll bet you someone left them out when they had the transmission out. These bars are supposed to keep them from twisting and cracking the case. I'm not sure I could explain this, but I have seen it, and this is what I got from them. Also; a broke, or worn motor support can do this. The motor supports may be weak, and you can tell by the engine will be sitting so low that the vehicle will have a vibration to it when under a hard pull. Also; Are your wheels all the same size? Do you have one size on the front and a different size on the rear? Do you have two different ratio differentials in the vehicle, as in the wrong ratio gear in one that don't match the other? If you have as an example a 4.11:1 in the rear end, and a 3.73:1 in the front differential? This will cause a bind and something will break every time. Glad to help out, Good Luck!!!
