I have a '64 F100 step side Someone put a 300 six in it with probably the largest 4 speed manual trans I've ever seen. I want to update to a manual trans with overdrive and would like to hear suggestions. Will not be looking for hi performance, just a practical combination. Also what might be helpful is what donor vehicles to look for. A 3 speed with o/d has been suggested but I don't know anything about that trans. or what to look for. Thanks
The toploader ford 3 speed ODs The 3 speed with R10/11 overdrive Both came in f100s. They can be tough to find. The one with the r10/11 can be used with a column shift. The other is a floor shift. Needs its own shifter but some have modified a regular 4 speed shifter. A 5 speed from a late 80s to mid 90s will also work. A ford t5 could be used with a mustang bell housing There are a couple 80s 3 speed ODs ford used Lots of choices for a 300. It shares the ford small block bell housing. There’s some spacer/adaptors to use T5s behind older bell housings Don’t use a SBF flywheel though. Mechanical, cable and hydraulic clutch set ups were used.
The best 3 spd+OD is the cast iron derivitive of the trusty Ford Toploader. I had one in a mid-'80s van. Also pickups had them. They have conventional external side rod shifting and came with a floor shifter. The ratios are fairly widely spaced, good for an engine like the 300 with a broad flat torque curve. I think the tag on the trans reads "RUG". There are also some aluminum case single rail shifter transmissions that are not as strong, but would be fine in a small pickup.
And goofy stuff like this AMC/Ford set up electric OD behind a 3 speed. Just picked up this one. Found a factory r10 set up and working a deal. This crap is out there when ya look
M5R2 (aka M5OD-R2) out of a 1988-1996 Ford F-150 with a 300 CID (4.9L) I6 or the 5.0L V8. https://en.wikipedia.org/wiki/Mazda_M5OD_transmission I've got 10 years and 37 states on one of these (off-topic 1986 Ford F150 - powered by a Cummins 4bt (3.9L) diesel engine). Note: (EDIT 1997) and newer have the Modular engine bellhousing pattern and do not bolt up to the 300 CID engine. Russ
Modern Drive Line has an affordable adapter to put a Mustang world class T5 behind your 300. To me it's a better choice than the Mazda derived trans. The RUG trans have issues with the cluster gear bearings because It is used in overdrive for many miles at a time.
There’s a HD ZF trans as well. Used in 3/4-1 ton trucks. For cruising, I like the t5 gearing The Mazda trans is a good choice but I like the t5 gearing better. The toploader (iron case) would be my next choice if not using a 5speed I’ve drove all the options listed but the r10/11. The 3speed ODs will do the job but there is a stretch between 2nd and 3rd. Not an issue for cruising. We pounded one of the iron case ODs on the street behind an FE and survived. I had the aluminum mid 80s 3 speed OD that lasted over 300k. Engine puked before the trans did. The later 80s-mid 90s truck 5 speed had better gearing that the 3 speed OD.
M5R2 is the best way to go behind a 300 if you are looking for a cheap 5 Spd OD. The large 4 speed you are refering too, is most likely a New Process 435 or BW T18 / T19. Commonly found in Ford F250's and F350's (along with numerous medium duty applications) in the late 60's to the mid 80's. Gear Vendors does make an Overdrive kit for both the NP 435 and T18 / T19. It is not cheap, although used ones can be found for a discount. Advanced Adaptors also used to make a manual dual range gear splitter that gets mounted between the trans and bellhousing for these Medium duty 4 spds that offered a 27% overdrive. They were about half of the GV cost. Production just stopped last year, so used ones can be found fairly easily. They do make for a big package though, here is one mounted to the front of the T19 that is in my '85 F350. It makes the poor Harbour Fright transmission lift seem tiny.
I have the M5R2 behind a 300 6 in my 56 F100. I could even use the factory hydraulic clutch- works great. I think trailer trash meant 1997 when M5r2s went to the newer bolt pattern. My M5r2 is out of a 92 F150. I had to modify the output shaft to add a speedo gear and get a tail shaft housing off a 87 M5r2 for speedo drive. Believe it or not the 88-90 or so on up used a speed sensor in rear end to run electronic speedo.
Welll, Yes... but be aware that there are two flywheel sizes - a 164 tooth used on the 300, and other V8 truck engines, and a 157 tooth flywheel used on small block car engines. You will need a flywheel with a zero (neutral) balance. Most V8 SBC flywheels have either a 28 in-oz or a 50 in-oz external balance weight. A SBF bellhousing (and corresponding block starter spacer plate) may be sized for the 157 externallly balanced flywheel. To use it on a 300 you must use a zero-balanced flywheel. I think the easiest one to use was the BOSS 302 engine. Good luck with your project. Post pics.
I’ve got a four speed overdrive top loader in an OT truck behind a 300 six! Outstanding road machine. I drove it many times from Muskogee to Ft Hood , Texas at 80 mph! Got excellent fuel mileage! That would be my suggestion. But don’t use high gear till after 60mph!, Bones
I believe the trucks used a gear drive speedo through 1990, with some strange speed sensors. My 1990 F150 has a gear driven speedometer.
Thanks for the input. When it warms up.....(might be a while). I'll start looking in salvage yards for a donor. Or maybe a used truck so I can test drive!
Don't use the ZF-5 mentioned. It is a big truck trans. It is called a 5 speed OD, but is really a 3 speed with compound low (granny low 1st gear is like 7 to 1 ratio) and an extra OD 5th gear. It did come factory behind 300 six, 460 V8 and the diesel V8s, all three with different bellhousing bolt patterns. It is a very large, heavy, strong, and not good choice for hot rod transmission. I agree the Mazda M5R2 is probably a good option for what you want. Plus should be fairly easy to find and reasonable cost.
If you were to look at the opposite side of those two transmissions you'll see that the 3+OD case has a cluster gear bump-out to accommodate the cluster gears to overspeed the output shaft.
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