Toploaders

TRush

Member
Nov 18, 2019
3
1
13
Kansas
I am helping a friend build 1967 Mustang Fastback. Originally it was an inline 6 and a 3 speed transmission. We found that the head was bad on the 6cyl and was able to score a 302 that had already been rebuilt by another friend for a reasonable price. Far less than the cost to rebuild the 6 cyl. The transmission is a toploader with the id code of RAN S 1. Based on the information I have found, that transmission was used in multiple cars and trucks with small block V-8's and 6cyl. We would like to make this car a 4 speed and I know the id plate I am looking for is a RUG or HEH. Looking at the case we have I see that the RAN S 1 Plate is riveted onto the case and the case has the 8 bolt pattern where it mounts to the bell housing. I assume that the case is the same whether it is a 4spd or a 3spd and Ford just riveted what ever code the transmission was meant to be on the case.

Can anyone confirm my assumption? If my assumption is correct, what does it take to convert the case we have to a 4spd and do you have any resources on how to go about doing it?

Thanks in advance!!!

Never mind :) http://www.mustangtek.com/transmission/Ford3speed.html Found a good website with photos and codes for toploader's and they are completely different cases. I guess that's why we do research!
 
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any nine bolt top loader four speed will work fine to replace a nine bolt top cover three speed.

as to the bolt pattern for the trans to bell housing mount, some top loaders came with dual patterns so they could be used in cars that had the tall narrow bolt pattern, or the later tall wide bolt pattern.
 
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any nine bolt top loader four speed will work fine to replace a nine bolt top cover three speed.

as to the bolt pattern for the trans to bell housing mount, some top loaders came with dual patterns so they could be used in cars that had the tall narrow bolt pattern, or the later tall wide bolt pattern.
Thanks for the info
 
there were several top loaders, the big shaft was for the 390-428 big block cars, then there was the standard small block toploader, and at least 1 that had a v8 input shaft and a 6 cyl diameter output shaft that required a different yoke, there were also 2 different bellhousing bolt flanges, some with 1 hole and some that would use both holes to accommodate different bellhousing/trans interface . So make real sure of what you need, I went through this song and dance, but it was 45 years ago, or I'd be more specific..The other thing to consider is the the toploaders have not been manufactured forever, so you may find one that needs rebuilding, I'm not sure anymore about the parts sources for them.. Worse comes to worse a BW super T10 may be a better way to go, or for that matter a world class T5.
 
You also can send your input shaft to Liberty Gears in Michigan and they will cut your input shaft and raplce the nose with new shaft made from 300M material and you won't twist it or break it. See the twist in the shaft. That's after 3 passes with slicks at the dragstrip.
I am taking mine apart and getting ready to have it done. Call them and ask for Paul. Phone # 586-469-1140
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RAN S1 is a 3.03 Toploader THREE speed. The main cases are completely different between 3 & 4 speeds and not interchangeable in any way, shape or form. You want to make sure your 4-speed Toploader has a 14-inch tailhousing with the rearmost mounting holes for the shifter to avoid having to use an adapter plate.