'80s Ford Truck help - Manual Transmission choices?

[zeitgeist57]

Hai guys...for my 1982 Ford F100, I've got the engine at M&M up in Delaware getting a rebuild. Anticipating getting that back in a month or so, I need to figure what I need to do with the transmission.

 

When I bought the truck from T.J. (00TypeR), it had the stock Ford 3-speed (3.03, "RAT-H" transmission) that originally had a column-shift, that was converted to a floor shifter. My original Cleetus was a '80s Chevy with a 3-speed column shift I had to convert to a floor-shifter; they get the job done but ultimately suck to drive for a long period of time.

 

Thankfully, T.J. gave me a Borg-Warner T19 in the bed that he and his dad had. This is an old-school 4-speed "toploader" that's fully synchronized. It looks to be in good shape, and the trans shop up by Doc's in Delaware said they would inspect it, and replace both input/output seals for $40.

 

I would LOVE to have an overdrive manual-transmission - like a 4-speed Tremec or even a 5-speed Ford/Mazda tranny from the F-150s - but my F100 has a manual clutch linkage instead of a hydraulic clutch setup. I AM TRYING TO DO THIS ON THE CHEAP, so offhand this is out of the question, even if I could trade someone both of my 3- and 4-speeds for a decent 5-speed.

 

However, the problem with the T19 is that it's got a fixed-yoke output shaft instead of the 3-speed's slip-yoke...and is a few inches shorter overall. Even if it's a simple swap (same flywheel/clutch/crossmember mount) I'm going to at least need to get a slightly longer driveshaft. Is that expensive for shops to lengthen a driveshaft? This is definitely not going to be a high-horsepower truck.

 

Any thoughts? My obvious inclination is to swap in the non-OD 4-speed T19, and lengthen the stock driveshaft to fit. This should retain the stock clutch linkage and flywheel, allowing me to resurface the flywheel and use the same 11" clutch kit. However, is the 5-speed really worth the cost/effort to get more gears and an OD, even if I have to figure out how to do a hydraulic clutch swap???

[Richard Cranium]

How much freeway driving are you going to do with the truck? How many miles per year will you drive it? My assumption is not a lot. Something tells me that the overdrive won't make a serious impact on the total cost of driving the truck per year. I'd go with which ever one your trans shop says is more reliable. I don't think a new drive shaft would cost that much.

 

Here is a question I was just thinking about. You're rear end has a standard yoke for a u-joint, and that 4 speed top loader has a standard yoke for a u-joint. That would mean the drive shaft would not have any way to slip back and forth. I think this would put an unacceptable level of stress on the u-joints and drive shaft overall since it has to be an exact fixed length at all times. I assume one end needs to be able to move a little to compensate for temp and chassis flex while driving.

[Buckeye1647545503]

What are the final drive ratios in these trans? if not a big difference it may not be worth it

[zeitgeist57]

How much freeway driving are you going to do with the truck? How many miles per year will you drive it? My assumption is not a lot. Something tells me that the overdrive won't make a serious impact on the total cost of driving the truck per year. I'd go with which ever one your trans shop says is more reliable. I don't think a new drive shaft would cost that much.

 

Here is a question I was just thinking about. You're rear end has a standard yoke for a u-joint, and that 4 speed top loader has a standard yoke for a u-joint. That would mean the drive shaft would not have any way to slip back and forth. I think this would put an unacceptable level of stress on the u-joints and drive shaft overall since it has to be an exact fixed length at all times. I assume one end needs to be able to move a little to compensate for temp and chassis flex while driving.

 

It definitely won't be getting a lot of mileage. When I bought Cleetus III (diesel Silverado), I thought I would drive it a lot more, and take the mileage off of the Passat and Corvette. That worked in Florida for awhile, but I stopped doing that once I moved back to Ohio. I don't have any plans on driving this Ford on long trips, unless it's for a purpose, and that would likely be hauling something where fuel economy won't be my primary concern.

 

I didn't think about the driveshaft...be curious to see what others chime in on that, and I'll Google it as well. More to come on that...

[351mach11647545510]

What year top loader is it? I'm pretty sure I have one that's slip yoke

[zeitgeist57]

My bad...It's a T18. I just ID'd it on my lunchbreak. Doesn't really change anything except for the fact that 1st is not synchronized. It's got the fixed-yoke output.

 

The 3-speed is a RAT-L "3.03" heavier-duty transmission. It's got the slip-yoke tailhousing.

 

Both have 10-spline input shafts. Just making sure

[zeitgeist57]

Guys, thanks for the ideas. I'm going to stick with the T18 4-speed (provided it is in good operating condition) and Columbus Joint and Clutch is going to resurface my flywheel for $26.50 and install a slip-joint on my stock driveshaft for around $200 (or less). That's the option with the least number of unknowns, and I still get a stout transmission with an extra gear.

 

Happy Thanksgiving!