Warford Overdrive Questions

lookin-backtexas

Senior Member
Is anyone running a Warford Overdrive in their Model AA truck? I just bought one and want to install it in my '28 AA Express. Can you give me a short tutorial on how to shift them and does this mean the truck will now have 9 forward speeds instead of the original 3? Also how much will it increase the top end speed? I have a high speed rear axle and am wondering if I can gain about 10-15 mph with the Warford.
Thanks

 
I believe those are all engineered for the 1930-31 chassis and four speed arrangement and will not fit in a 1928 AA chassis without a lot of cobbling. It is a compound transmission, so why not just use the proper 1928 two speed behind the 1928 3 speed?

Warford overdrives actually were introduced in 1923 and used on TT's; patented in 1926. I have several AA's with Dual High auxiliary transmissions however they are considered underdrives to produce more pulling power and lower speed; the whole point of installing an overdrive is to increase speed. I just bought an early '28 AA which has the Warford overdrive transmission where the normal Dual High would be. Just trying to learn more from those who own one.
 
There might be more help regarding Warfords over on the AA club forum. I had always wanted one when I had my AA but could never find one. 30-31 Warfords are supposed to be more common than the 28-29 ones, but I would say any of them is a pretty rare piece, and the couplers needed are even harder to find. You really scored to find a 28 Warford complete mounted in a chassis. I had the 5.14 gears in my 31, but thought 6.6 worm drive was the only choice in 28 so I'm not sure what you mean by you have high speed gears.
I could do 45mph with 5.14 gears no overdrive. I think many AAers overlook the consideration of wheel balance on these rigs. I found it hard to get the truck to run smooth at the higher speeds with such heavy wheel/flap/tube/tire assemblies, and I was running duals on the rear.
Yes the truck can be made to run higher speeds with the overdrive but I think it will take alot of fooling with rim and tire combinations to make the truck pleasant to drive at those speeds.
You may still find 45 is the sweet spot but at least the engine won't have to spin so fast.
 
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I believe those are all engineered for the 1930-31 chassis and four speed arrangement and will not fit in a 1928 AA chassis without a lot of cobbling. It is a compound transmission, so why not just use the proper 1928 two speed behind the 1928 3 speed?

Anybody should know that the Dual High two speed is an underdrive, not an overdrive.
 
There might be more help regarding Warfords over on the AA club forum. I had always wanted one when I had my AA but could never find one. 30-31 Warfords are supposed to be more common than the 28-29 ones, but I would say any of them is a pretty rare piece, and the couplers needed are even harder to find.

I have a '28/ '29 Warford in my 1930. Finding the necessary parts wasn't difficult.
 
Is anyone running a Warford Overdrive in their Model AA truck? I just bought one and want to install it in my '28 AA Express. Can you give me a short tutorial on how to shift them and does this mean the truck will now have 9 forward speeds instead of the original 3? Also how much will it increase the top end speed? I have a high speed rear axle and am wondering if I can gain about 10-15 mph with the Warford.
Thanks

The truck will have 9 forward speeds and three reverse. Easy to shift but technique is different as the trans oil heats up. Most of the old Warfords I worked with are noisy in high (but not all). You can replace the output gear and this will help but if it's really worn the only way to quiet it back down (originally it was quite in high) is to hard-face chrome the gears back to spec. They are very useful at times, I can do 55 mph all day in my express but life is better at 45. Useful in the mountains as you can put the truck in 2d over and not collect fifty cars behind you.

ron
 
Am running a Warford on 1930 dump with four-speed trans and high speed rear end. Not certain of MPH increase in overdrive (never checked) but use "over" for most driving except with a load then I generally run in "direct". "Under drive" is a VERY low range which I seldom use. Have tried shifting the Warford "on the fly" with poor results (lots of grinding) a good chance I don't know what the heck I'm doing (I ain't no trucker!). I usually select the gear range I anticipate I will need when I am stopped. With the four-speed trans there is no problem starting from a dead stop in "first / over" (trans in "first" gear, Warford in "over"). Hope this helps a bit. Good luck!
 
28-29 Warford 2 speed or 3 speed units had 6 spline input and output shafts. The 30-31 Warfords had 10 spline input and output shafts. There are other interior differences. The way they attached to the Model AA transmission is also different.
The 30-31 Warford was also available as a SWB unit or a LWB unit.
 
I had the 5.14 gears in my 31, but thought 6.6 worm drive was the only choice in 28 so I'm not sure what you mean by you have high speed gears.

The worm drive rear axle was available with either a low speed with a 7:25 to 1 ratio or a high speed with a 5:17 to 1 ratio.
 
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