I'm building a 292 for my '55 F100. It currently has the original column shifted 3 speed. I've read articles about the '81 0r '82 ford three speed OD trans. I found two of them in junkyards but they are in an '85 and an '86 6 cyl pick up. Is this the same trans?

I found a ton of 4 speeds in these early to mid 80's trucks, If the 3 speed OD is the wrong one could I use one of these 4 speeds? Would I be happy with it?

Just FYI I'm switching to a 9 in with what I beleive is a 3.25 or 3.55 rear gear. I'd like to be able to drive this truck on the highway and also occaisionally tow a loaded car trailer. Not sure I want to go to all the expense to put in a t-5. Any help would greatly be appreciated.

Part numbers etc would be greatly appreciated as well so I know what to ask/look for at the bone yard.

 

I think those transmissions are the SROD transmissions. Do a search of this forum and you'll find discussions of the various transmissions and how they fit. If I recall correctly, the front bearing retainer is slightly too large. You'd have to have it turned down to fit the bellhousing. Some transmissions had a dual pattern drilled into their flanges. One of these would bolt up to your bellhousing. Then you'd have to fit a shifter to it.

If you decide to go with a T-5, I'd get a Mustang WC 5sp. Then swap on either an S-10 or Jeep T-5 shifter to help with seat clearance.

 

Well, when you ask about 4 speeds, I don't know whether you are referring to 4 speed car or truck transmissions...

For any truck 4 speed, they are large and heavy, and have a shifter that sticks up thru a hole in the floor. They have the same three top gears as a car 3 speed, but the lowest gear is a "granny" gear in the 6:1 ratio range. If you are using your truck to work with, like pulling heavy trailers, that's what you need. To use a truck 4 speed, you need that bellhousing, which has a 5 1/8 register hole in it for the input bearing retainer. When you shift one of these, you wil know why people said "it shifts like a truck." They are meant for work, not play. The T98 and the T18 are commonly encountered versions in Fords.

If you are talking about car transmissions, note that car 4 speeds generally have ratios around 2.5, 1.8, 1.3 and 1 for 1st, 2nd, 3rd, and 4th.

The SROD was a modification Ford made to their excellent toploader 4 speed for the fuel-mileage needs of cars and light trucks after the "energy crunches" of the 70s. They did this by taking 3rd and making it an overdrive, and then modifying the linkage to give the right shift pattern. The linkage on the SROD is all enclosed. One bad thing about this is that the ratios are now something like this: 3:1, 2:1, 1:1, and 0.7:1 -- there is a big gap between 2nd and 3rd -- that 2 to 1 ratio jump -- that makes you feel like you are missing a gear all the time.

They came in many vehicles, but you must remember that Ford cars and 65 and up trucks used a car transmission with a 6.5" input shaft length. Ford trucks of 64 and before used a 7 1/8" input shaft length, and these can all be found in trucks with engine mounts on the bell housing. The later car/truck trans will fit the earlier truck (except for the input bearing retainer: newer ones have a 4.85 diameter and must be turned down to 4.675" to fit the older bellhousings. Use allen bolts to gain some clearance, too.) but the input shaft will barely fit into the pilot bearing and the splines will only barely engage the clutch disk.

There is an SROD that does use the longer 7 1/8 input shaft, and those came on the 80s versions of 5.0 Mustangs, before they started putting T5s in them. That is what you should use if you want an SROD.

If you use the 5.0 Mustang SROD, then you need to take care of two things: the shifter and the clutch cross shaft mounting. SROD shifter tubes came in a number of lengths, from putting the shift lever at the end of the tailshaft to putting it right behind the actual gear case. If you are running bucket seats in your F100, you will need to cut the floor for the shift leaver. IF you have bench seats, you'll need to cut the shift lever off and reach under the seat to shift. But, there was a version of the SROD that came in Jeeps -- it had a shift lever that sticks up out of the top a a modified gear box cover, just like big truck 4 speeds used. If you get one of these and put it on your Mustang SROD, the shift lever will come thru the floor in about the same place as the truck transmission lever does.

All of the Ford manual transmissions that came in F100s had two mounting bosses for the clutch pedal cross shaft to mount to and pivot on. You will need to rig something up to mount your clutch pedal shaft to the SROD.

 

my questio is will a T10 4spd from richmond trannys work on the old 292, and can you get a good performance clutch that will work with it.

 

Well, like I said in my post above:

You also have the input bearing retainer issue to deal with, as I also outlined, along with an inner mount for the clutch pedal shaft.

You'll need a new driveshaft.

Chances are, you'll need to run buckets and mount the shifter thru a new hole behind the stock floor access panel.

You might be able to use the front bearing retainer on your old 3sp, if it is a BW T89.

If not, you will need to come up with a throwout bearing that works on the smaller sleeve and engages the clutch fingers.

But look at how much spline you'll have sticking into the clutch disk! Look at how much of the input journal you will have sticking into the pilot bearing!

I'm sure you can back out of the driveway, but I would never trust it.