Can't find any info on this bolt needed

[bucket]

The big thing I remember from back in the day was that the Asian vehicles favored even number metric wrench size and north american vehicles favored odd number wrench sizes (with the exception of 10), probably holds true through today.

At least in the 80's and 90's, Ford used literally every size in a well-equipped metric socket set. No joke. Some were far less common, but they didn't discriminate. And I'm not talking just about 5.5mm. They also used such oddballs as 4mm, 4.5mm, and 9mm.

 

[Beast496]

My 85 TH400 tail housing to trans mount bolts are M10x1.5, in about a 1 inch length(or would I say 25.4mm length??:haha)

 

[bucket]

My 85 TH400 tail housing to trans mount bolts are M10x1.5, in about a 1 inch length(or would I say 25.4mm length??:haha)

All joking aside, metric bolt lengths mostly come in 5mm increments when being purchased at most places. From what I've found, many OE manufacturers tend to stick with that same trend, besides engine fasteners.

 

[bucket]

And I forgot, Ford also used hardware with 20mm heads. And also pinch-loc nuts that were pinched so much, they weren't really any exact size at all. Those were found on truck and van bumper bolts.

 

[Turbo4whl]

I remember GM doing that in the 80's but didn't think it has affected new parts for earlier rigs. Now I need to go reef on mine and see if I have proper thread engagement. Great heads up

Turbo hydro 200s,700r4s,and 200r4s should be metric. Turbo 350s and 400s should not be metric. Beings he is using a 84 and 87 truck my 1st assumption is he is 700r4

For anyone that does not know why you find standard hardware and the Unified Metric hardware on the squares, is the USA conversion. The 1975 Metric Conversion Act, dictated any new items designed be metric. Existing systems remained as they were.

So as @Ricko1966 stated the newer transmissions were metric, but still used 3/8 standard bolts to the engines. The Metric Board was abolished in 1982.