So I had a 700R4 rebuilt about 6 months ago, and just got around to installing it in my blazer. Less than 700 miles later (666 to be exact:mad3: ) I'm driving to work at 70 mph and it is as if someone reached down and put the trans in neutral. After getting off to the side of the road, I check everything out. Trans fluid good, no busted u joints, nothing at all looks wrong. Well, I managed to get it moving in 4 low, and got it off the expressway. Had it towed to the trans shop to get it checked out, and they say that it will no longer even move in reverse. They are still checking it out, but say it doesn't look good. The build was as follows; AA adapter shaft to mate to a NP203 transfer case, extra friction bands, corvette servos, new valve-body reworked to lock converter upon shifting into OD, new torque converter, and all sorts of other goodies put in. I was told this trans would take pretty much anything I could throw at it. I had never beat on the truck, and had only had it offroad once. I was still trying to give it a good shakedown to make sure nothing broke down offroad. So, is this something I could done to the trans, or do y'all think it was something the builder did wrong. Thanks for the help and advice.

Nick

Depends on what happend... Even thou it had all the goodies in it. If the TV cable wasn't set right or not on it would have burned up that quick. Did you prime the torque convertor before installation? If not that could have fried and took out the convertor.

The throttle valve cable was adjusted by the trans shop. As far as the torque converter, the shop inserted it into the trans to ensure it was installed correctly and mentioned nothing to me about priming it. Prior to starting, I filled the pan with fluid, and once the motor was running at idle I continued to fill the pan until it was full. Should I have done differently? I guess I should hear from the shop tonight, I just fear that they are going to try to screw me. Thanks for the help.

sounds like you did everything right. if they adjusted the tv cable then they should have done it properly.

if the cable was not adjusted properly the shift into 4th would have been noticeably "soft" and it would have slipped before loosing 4th. since this happened all of a sudden i would assume parts failure. either way, if it was a complete rebuild like you mentioned then it should carry a 12month/12,000 mile warranty and you should be covered.

chances are they'll have to pull the trans and tear it down to see what's up.

when you had it built did they install an HD sun gearshell (called "the beast")? if not, i would ask them to install one when they put the trans back together. might actually be the cause of the problem.

when you had it built did they install an HD sun gearshell (called "the beast")? if not, i would ask them to install one when they put the trans back together. might actually be the cause of the problem.

That was my first guess, was that the drive shell broke at the splines

Yes, they installed a HD sun gear shell. From my understanding, everything that could have been beefed up internally was done. I spoke with the trans shop yesterday, and they asked me to cover the labor of pulling the trans since it was not in the truck the first time it was built. They also said they were more than willing to stand behind their work. Sounds like they're gonna make good of a bad situation. I guess I'll know more of what happened once they get it apart. I'm kinda curious, because I'd like to know so that if it's something I'm doing I can make sure and not do that. Thanks for the replies guys.

Nick

That was my first guess, was that the drive shell broke at the splines

Only 2nd, 4th, and reverse run through that shell. If it fails, it still leaves you with 1st and 3rd.

So I heard back from the trans shop today, and the Advance Adapters output shaft broke in half. Kinda sucks. Has anyone heard of this happening before? Do I have any options other than the AA shaft?

Ok, so it was not the output, it was the input shaft. Trans shop is coming good and warrantying the trans. But does anyone know what would have caused the input to literally snap in half?? Any input is appreciated. Thanks.

i would think that the input was already cracked when they did the rebuild. it's not uncommon for the input to crack between two of the lube holes. but it's not common enough for you to have to worry about it. the chances of it happening on the same rig or to the same owner are slim to none.

but if you are worried about it, get a billet input shaft from art carr.

it's not uncommon for the input to crack between two of the lube holes.
That's exactly where it cracked at. At least that makes me feel better to know that I didn't personally break it. Thanks for the input.

Nick

makes me feel better to know that I didn't personally break it.


yup, it would be almost impossible for you to break that on purpose. glad to hear it's covered under warranty.:)