M1008 (th400) vacuum modulator

[VLAD1234]

My 1986 M1008 has been shifting hard so i tried to replace the vacuum modulator. I bought a replacement for the TH400 at Standard Auto Parts and tried to install it however the shaft that is to be inserted into the transmission was just slightly too wide and would not fit. I also noticed the old vacuum modulator was somewhat larger than the new one. I returned the part and every way they looked up the part it stiil referred to the same one that would not fit. Any thoughts? Any recomended replacement parts that will work or surplus N.O.S. sources? Thanks

 

[Warthog]

Did you give them the GM part number from the TM 9-2320-289-34P?

GM 359917

Here are some of the many threads covering this

http://www.steelsoldiers.com/cucv/57466-replacement-modulator.html

http://www.steelsoldiers.com/cucv/57945-th400-modulator-installation-help.html

http://www.steelsoldiers.com/cucv/52993-replacing-transmission-modulator-vacuum-lines.html

 

[VLAD1234]

I did not have the part #'s at the time. I will try again and investigate further using the thread links you provided. Thanks so much for the help.

 

[Cucvnut]

The B&M modulator fits also if u want to try that route.