Wire Fox
Well-known member
- 1,252
- 161
- 63
- Location
- Indianapolis, Indiana
I'm wanting to do things right with my transmission and have an easy platform with which to rebuild it with minimal swearing involved. The official mounting fixture for use is the J-8763-B, which should be able to handle the TH350, TH400, 700R4, the 4L60E, and some others; however, I can see from the -34 TM that there's an adapter plate that is required for use with the 4L80E (image attached). It appears that this plate is designed to offset the mounting point on the fixture by less than an inch. For anyone with experience rebuilding these, how critical is this offset adapter?
I ask less because I'm trying to skate around buying a $40 adapter plate, but more because I'm actually looking at an aftermarket holding fixture. A seller on ebay has a nice C-Frame fixture that's designed to bolt onto an engine stand instead of a workbench, which will make my life way easier. He sells a model that supports everything the J-8763-B supports and he also sells a second model that adds support for the 4L80E, along everything that first model supports. The images show no adapter or sliding adjustments to accommodate multiple offsets, but the seller is adamant that it supports everything he claims without any special adapters. Does this sound like it may actually be reasonable? Is the offset the adapter for the J-8763-B provides an unnecessary piece built for perfectionists that demand a perfectly-rotated transmission while working, or is it actually essential to ensure the transmission is completely secure and poses a safety hazard if one does not use it?
Ultimately, I only need to be able to rebuild 4L80E transmissions, but I know that as soon as I go out and spend $160 on a holding fixture and $50 on an engine stand, I'm going to end up with something in front of me that's going to have a TH400 or 700R4 that needs some TLC and I don't want to be SOL.
I ask less because I'm trying to skate around buying a $40 adapter plate, but more because I'm actually looking at an aftermarket holding fixture. A seller on ebay has a nice C-Frame fixture that's designed to bolt onto an engine stand instead of a workbench, which will make my life way easier. He sells a model that supports everything the J-8763-B supports and he also sells a second model that adds support for the 4L80E, along everything that first model supports. The images show no adapter or sliding adjustments to accommodate multiple offsets, but the seller is adamant that it supports everything he claims without any special adapters. Does this sound like it may actually be reasonable? Is the offset the adapter for the J-8763-B provides an unnecessary piece built for perfectionists that demand a perfectly-rotated transmission while working, or is it actually essential to ensure the transmission is completely secure and poses a safety hazard if one does not use it?
Ultimately, I only need to be able to rebuild 4L80E transmissions, but I know that as soon as I go out and spend $160 on a holding fixture and $50 on an engine stand, I'm going to end up with something in front of me that's going to have a TH400 or 700R4 that needs some TLC and I don't want to be SOL.
