Can anyone identify this auxillary trans? The only marking I can find on it is 18171. It's currently in my '26 TT. Thanks.
Chevrolet adapted to Model T Ford
Makes sense because they had to cut and bend the seat box to fit the shift rod in
Big clue is the 2 mounting flanges, one on each side of the transmission case, each side has 2 bolts. Transmission in this picture probably has different shifter than yours, it varied with model application.
Does this trans override the original transmission? My bands don't look too bad on the brake and reverse, they clamp down when depressing pedals, but neither engage.
I should add that neither engage while truck is running. The drive band is shot and doesn't engage either.
Cool I have one on my 26 sedan I'm restoring now. I am also curious if any one has a working one in there vehicles now on how it affects driving.
They are a standard direct, second, and low, plus reverse. They were popular to adapt to a model T because the U-joint and torque tube connections were close enough to be adapted easily. Usually, they were put in the normal direction, and basically eliminated the planetary transmission from usual use. Many people left both functional, so they could choose lows and reverses, or have a "stump puller" gear if needed.
I have seen a couple such transmissions, slightly modified. and turned around. With the low and reverse gears removed, the original direct and second gear becomes a direct and very high overdrive. I don't know the exact ratio of Chevy's second gear, however, most second gears on standard three speed transmissions are roughly 50 percent. That is 2 to 1. When turned around, it becomes 1 to 2, or 100 percent over! A bit steep for most Ts. It could be good with 4 to 1 gears as a highway gear for a fast speedster. Or maybe could be a nice poor-man's high gear in a 7 to 1 TT.
I always wanted to try that one myself.
Gale B, One other thing. From your photo, I am not convinced of what I am looking at. While one view does appear to be a standard common Chevrolet transmission? The other view does not. There is something extra there. I am not sure, but it looks like maybe a power take-off. It may have been something available for Chevy trucks, and therefore easily adapted along with the transmission into a TT.
I have a chevy transmition that was adapted to a T. I dont know what the numbers are on it but it has a bow tie cast into it with the numbers. Did they make an adaptor for these or were they on their own to make it work?
Would any think that their would be any plus to keeping it the way it is or going a different route
The problem with the gears as they are now is that I have no clutch, so I have to grind it into gear from a standstill. I would think with the T trans working properly, I could start off with that, then utilize the other gears at speed so they slip in without all the grinding.
How much of the T transmission is functional? The T clutch is adequate for shifting the various auxiliary transmissions. When at a full stop, the T tranny brake will hold the input to the Chevy trans making it easy to put into gear. However, generally speaking, with secondary transmissions in play, the planetary transmission brake should NOT NOT NOT be used as the sole primary or service brake. So many Ts and TTs have had the planetary brake eliminated.
I have had three Ts set up that way, with the pedal set up onto better rear wheel brakes. Unlike some in this hobby, I do NOT like the planetary brake set up on the same pedal as the rear brakes. There is too much possibility of wear creating a condition where disaster is a likely probability.
So, on my cars where the planetary brake did not function, I use the reverse pedal to break the clutch loose and stop the input gears from spinning. It is a little tricky. Press the clutch pedal (or use the brake handle), then press the reverse pedal until you can hear the transmission turning things telling you that the clutch is doing its thing. The problem now is, the input gears to the auxiliary transmission are still turning, only in the opposite direction. Solution? Hand on shift lever, lift foot off of reverse pedal. The clutch's drag will quickly begin to turn the input gears back to forward direction. As this happens, the input gears will be stopped for about a half second. At this moment, put the auxiliary transmission into gear. One should with a little practice be able to do this without any grinding of gears.
Wayne, My clutch and planetary brake do not appear to be working since at no position does the clutch allow me to shift the transmissions into gear without grinding, and the planetary brake doesn't seem to even slow it down. Sounds like I need to start from square one and check/repair everything from the inside out. I wish I had more experience with the workings of the T. I can tear into a sixties car without hesitation, but for some reason, the T intimidates me.
Ts can be intimidating. They are simple, but alien to almost anything built since. The first thing one has to do, is forget most of what you know, other than the really basic stuff.
The T clutch is an oil bath multiple disc. They are notorious for sticking together inside. If your T sat for more than a few years, that could be half your trouble. Proper adjustment is critical for a good nearly free neutral. There have been many good threads about how to do that adjustment. But I can't find them, and never have been able to explain that "how to do it" myself. I just get in and adjust it and they work.
If the T has been sitting for years, changing the oil and running awhile (about three or four times, change, run, change, run, change, run) (cheap clean oil is good for this) can help flush the gunk out of the clutches.
You should also look inside the transmission to see how much is in there.
Thanks for the advice. The trans looks complete and clean, but the forward band lining appears to be almost gone and the band is adjusted so the spring is completely compressed. I've ordered new linings, springs, etc., and I am going to start flushing with oil now that it is running. I got some carb studs to put in when I pull the pan access cover so that the inner flange/horseshoes don't become misaligned. Unfortunately, the senior park I live in will not let me work on it here, so I am having to do these repairs in a flat spot in my pasture. Not the best environment to say the least. Adversity builds character...