Speedo Cable Question

Bruce Botti · #1 (**permalink**) 09-13-2001, 04:33 AM

Hello to all. I have been getting conflicting answers to my speedo question when I call around, so I thought that I would ask the experts. I have a Tremec TR3550, Jag 3.54:1 rear, and a mechanical Stewart Warner Gauge. Which cable/driven gear do I use. Some have told me that the Toploader setup would work (obsoleted by Ford 8 months ago). Others have said that the T5 setup from a Mustang would work. What gives?

Thanks,
Bruce Botti

tim · #2 (**permalink**) 09-13-2001, 01:49 PM

Bruce, get a Ford Motorsport catalog and use the information in the transmission section to figure out the tooth count of the driven gear. They also have part numbers for the gears and have broken it down into standard shift and automatic transmissions. I went to the local Ford dealer and ordered the gear I needed. The tremec is a replacement for the t-5 so the speedometer driven gears will interchange.
Tim

Bruce Botti · #3 (**permalink**) 09-13-2001, 08:01 PM

Tim,
Thanks for the info. Do I need to buy the electronic portion (I have a mechanical SW gauge)? Or can I just use the cable and the driven gear like on a toploader? In looking at the Tremec it appears that I can.

Thanks again,

tim · #4 (**permalink**) 09-13-2001, 09:15 PM

Bruce, you can use a standard cable like the ones used in 65-66 mustangs. They actually have the 5/8-20 threaded end that should match your SW gauge. I measured my car for the length cable I needed and went to the local NAPA store and got in there catalog. I found a cable within a couple of inches in length with the corect ends. The transmission end of all ford cables to my knowledge are interchangable. I think the actual aplication was for a ford car with cruise and the cable went from the transmission to the control box under the hood. I can find a part number if you need it, just let me know.
Tim

Bruce Botti · #5 (**permalink**) 09-14-2001, 07:15 AM

Tim,
I would appreciate the part # if its not too much trouble.
Thanks!

Dave Samson · #6 (**permalink**) 09-14-2001, 01:32 PM

Bruce,
I recently replaced my T5 with a Tremec TKO using a Smiths mechanical speedo.
The cable was reused and the tranny speedo housing fitted too, I only replaced the speed gear which is not interchangable.

tim · #7 (**permalink**) 09-14-2001, 03:49 PM

Dave, I would like to know why you say the speedometer driven gear is not interchangable? Ford only offers 2 types of driven gears (manual & automatic). What did you use for a driven gear if you didn't use a manual transmission gear? Some transmissions do have different tooth count drive gears in them. Maybe that was your problem.

Bruce, I,ll send you the part number when I get home.

Tim

Dave Samson · #8 (**permalink**) 09-14-2001, 05:25 PM

Tim,
I don't have any part numbers but I can tell you that the plastic gear that fits into the Tremec tranny is quite different in angle and tooth shape from the T5 .

tim · #9 (**permalink**) 09-14-2001, 06:02 PM

Dave that's funny, I've got a T5 driven gear in my tremec and I've had no problems at all. I wonder if Aussie stuff is different??
Tim

PNJSNAK · #10 (**permalink**) 09-14-2001, 06:31 PM

Bruce: Check out the speedo cable from Lokar. Less than $40 and you can cut and fit to length. Uses standard Ford driven gear. For your rear end should be black in color. I used it with my T5 and VDO gages worked great.
Jim

Dave Samson · #11 (**permalink**) 09-14-2001, 06:41 PM

I bought a standard Tremec TKO for Fords from the USA so I don't know what the deal is but with an 18 tooth gear my mechanical speedo is absolutely accurate up to 120 mph (as fast as I've test it using my GPS for calibration), running on 27" tires and 3.45 : 1 differential.
Sorry I can't help more.

Bruce Botti · #12 (**permalink**) 09-16-2001, 07:57 PM

Thanks for all the help...both here and via private e-mail!