What is the differance between the th350 trans and the th400 and which is better for a 455 engine? also what is average cost to rebuild a 350? Thanks in advance GARY (58Sled)
TH400 is the best trans ever built for strength due to its design. If you are going to build a serious engine, go with a TH400. There is a reason why all 455 engines came with TH400 behind them. Cost to do a TH350 for a 455 and a TH400 will be very close since you have to upgrade the TH350 to handle the 455 torque
A "Street/Strip" (Heavy Duty) TH350 Rebuild, will cost you around $250, if you have all the tools to Do It Yourself, and $400-$800 to have it done by a Transmission shop or to Buy one from a Transmission Manufacturer (B&M, TCI, etc.). The TH400 may be the "stronger" of the 2, but is becoming obsolete, with the Overdrive Transmissions becoming more popular with Strength and Reliability (TH200/4R, TH700R4, 4L60, etc.). Why "limit" yourself to 3 speeds, when you can have 4 for almost the same cost ($800-$1,200)!
