[Niapym]

i'm switching a 3 speed out for a 4 speed in my el camino, and the bolts for the trans mount won't fit in my new trans. the bolt hole is just bigger than a 3/8, but a 10mm course won't fit either. any ideas?

 

[stu]

The next larger size is 7/16 or 11mm.

 

[troy-curt]

Gm trans. mounts are 7/16 standard thread, until they went to metric.

Troy

 

[Crosley]

if the bolt hole is slightly larger than a 3/8 bolt.... it should be a 10mm x 1.5 thread

 

[Niapym]

threads

so after trying a bazzillion bolts that i had in the backyard, i realized the threads in the trans were flattened. i'm guessing whoever had it before me put a 3/8 bolt in and it bounced around and destroyed them. so i threw a 10 x 1.5 (i should have just done it to begin with) and it is working fine. i was this || close to drilling it and tapping a 7/16.

 

[Crosley]

good to read you have it fixed.

generally if the 10mm bolt hole is buggered up, a 7/16 tap will thread in and cut new threads easily.

I use STP as a lube for cuttin the threads