904 trans mount bolts

[2-66 Cudas]

Anyone know the bolt size going through the mount up into the trans case? Looks like 7/16 - 14 thread but how long? Went through some of the bags of bolts I got with the car, no luck.

 

[Woods74]

7/16 coarse sounds right, they are about 1 1/2, a good trick for depth is to take a screwdriver and stick it in the holes. Put your thumb on the mark, there you go.

 

[TrailBeast]

Yep, 7/16 x 14 x 1.5 inch lenght

 

[fishy68]

I have seen 1" long in them too but I prefer to use as long as possible since their going into aluminum.

 

[TrailBeast]

I have seen 1" long in them too but I prefer to use as long as possible since their going into aluminum.

Yep, the factory bolt is about 1 inch and I always thought that was dumb.

 

[fishy68]

Yep, the factory bolt is about 1 inch and I always thought that was dumb.

Probably save .02 for each bolt used, never mind it's just barely long enough to work rotest:

 

[krazykuda]

I have seen 1" long in them too but I prefer to use as long as possible since their going into aluminum.

If you have enough threads available in the hole, then use the longer bolt if it won't bottom out...

General rule for minimum thread engagement is 1 1/2 times the bolt diameter. So a 1/2" diameter bolt should have a minimum of 3/4 inch of engaged threads. But for heavier loading, it's better to get the extra threads if you can.