T-170 3 spd with OD transmission swap problem

[Matt in Alameda]

I have installed a 1985 ford truck t-170 3 speed OD transmission in my 1935 Ford 5 Window coupe. I had to shorten the torque tube by 2" to compensate the longer transmission. After it was all together I realized the the shortened torque tube has pulled the speedometer turtle back into the floor tunnel making it impossible to hook up the speedometer cable. Has anyone done this transmission swap in a 1935 or 1936 Ford? If so, how did you fix the speedometer hook-up problem? Thank-you for any help you can provide,....Matt in Alameda

[Newc]

Hi; Auto instrument repair shops can make a longer cable or even an extension. These shops are gradually disappearing unless they can repair the modern digital/electronic modules. newc

[V8COOPMAN]

About the only thing you can consider is to rotate the torque tube (and turtle) 60 degrees toward the driver's side so that the turtle is not on top any more. Yes, you'll have to move the mount for the radius rods, and possibly address the notch in the torque tube flange on the bottom pertaining to lubrication. If you've read our T5/TORQUE TUBE thread (click on bottom left below), you can see that this is what we did while shortening the TT on HEARD's '35 chassis. DD

[my4dv8]

Down under we a have a small cable shop that seems to be able to make any cable you require . Though with the ford you may need to supply a donor cable for the ends.
I did get an instrument shop to make a cable for me also, they probably went to the cable shop!

[johndee138]

Hey Matt, I finally got mine installed. If you haven't already welded the shortened tube , I would rotate the T Tube so the turtle mount is positioned counter clockwise this will put the threaded output on up to 3 or maybe 2 o'clock position, it may even take the 1 o'clock to really clear. I did not think about this when I did mine and had to hog out some of the center section where the turtle contacted the center section with a sawzall to get the speedo cable connector on. The amount I took out wasn't a lot but I had to cut and re cut till I could get the fitting connected. Didn't want to cut too much. It WAS a bitch to do but ........now it's just a memory!
Hope I can save you some grief!

[rotorwrench]

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Stewart Warner made 90 degree adapter gearboxes for a lot of applications back in the day. I don't know if they fit the early ford turtle & drive but It wouldn't surprise me if they did. If it was re-clocked then something of that nature may help re-route the cable.

[johndee138]

The problem is the turtle snout almost touches the saddle that runs under the T tube when you use the T170 tranny (longer than the Ford crashbox by the 2 inches) cause it pushes the front bell of the Tube to the rear 2 inches and it gets into the saddle support where the cross member joins together.

[johndee138]

The solution would be to clock the tube when shortening it and relocating the radius rod mounts.

[Ol' Ron]

I understand the need for an OD transmission, for today's driving. Nice to drive along with out the engine screaming. However the expense of modifying the trans and drive shaft for an out dated read axle is beyond my thinking. Be different if you were trying to keep it original. The trans could have been installed with a later rear open drive rear and rour problem is solved. I did that to my truck. and my speedometer works just fine.

[slowforty]

I know a fellow that spent almost a $1000 putting an overdrive trans in his car. He only drives it a 100 or 200 miles a season. I hope he lives long enough to get his money back.I figure I can buy an awful lot of gas,for $100, even at $3.50 a gallon.

[JM 35 Sedan]

I've always wished for a 3 spd with OD conversion that I could drop in and bolt up in my stock 35 fordor sedan w/o the need to modify anything. While wishing, hoping, and waiting for this transmission conversion, I decided to go with a set of 3.54 rear gears, which seem to be working very well.

[tjw]

T 170 trans converted.

[rotorwrench]

These conversions have had some popularity on the model A cars for quite a while. They have been creeping into the later V8 cars over the years but they are getting harder to source in the good ratio. New replacement gears are not available for them now. Folks that build them & modify them have to hoard the good parts. This is going to be a problem for them eventually unless some company steps up to the plate to manufacture new parts. They were made at the Tremec plant down in Queretaro, Mexico and they haven't made parts for them in years.