Got GPS speedometer, What to do with Speedo cable?

[mlobster]

Hello! Quick question for you guys with the GPS Speedometers. I bought a GPS speedometer from speedhut and I am currently installing all of my new gauges. Since the GPS speedo doesnt need the speedometer cable, what do I do with it? I would just remove the cable, but what would I use to plug up the transmission? Please let me know what my options are or what you guys have done to solve this minor issue. Thanks in advance!

[Gary in NJ]

How many people are using GPS speedo's in their S30's? My guess is 1; Mr. mlobster.

[beermanpete]

Nothing. The speedometer drive is sealed separately from the cable. You can simply remove the cable and drive.

[Arne]

Nothing. The speedometer drive is sealed separately from the cable. You can simply remove the cable and drive.

In a perfect world, this may be true. But in my experience, most of the o-rings that seal the speedo output on the transmission are leaking by now. At the very least you'll want to remove the speedo drive and replace all the o-rings, and then watch it carefully for leaks in the future.

[EScanlon]

...I would just remove the cable, but what would I use to plug up the transmission?...

Nothing. The speedometer drive is sealed separately from the cable. You can simply remove the cable and drive.

In a perfect world, this may be true. But in my experience, most of the o-rings that seal the speedo output on the transmission are leaking by now. At the very least you'll want to remove the speedo drive and replace all the o-rings, and then watch it carefully for leaks in the future.

Those of us in the PDX area, recall how Arne would casually mention that he was going to remove his Transmission, disassemble it, "change a few things", re-assemble and then replace the tranny in the car before going out on a cruise .... in just a couple of days (sometimes one!). And this happened not just once or twice, but several times. (In all fairness he was chasing a bit of a knocking sound.)

That being said, I think he's modestly saying... Huh? Nut-Nuh!!! to Beerman's post.

My non-mechanic thought is, if you don't mind destroying the sheath for the speedo cable, is to remove the cable and sheath assembly, cut off the end that plugs into the transmission after removing the speedo cable inside, and either have the plug hole brazed where the sheath ends (best option) or use some form of heavy/strong epoxy (JB Weld or the like). The intent being to PLUG the hole where the Speedo used to connect to.

FWIW

E

[cygnusx1]

The speedometer cable serves ZERO sealing function as is. If you have oil there, your oil seal and/or O-ring have failed. That said, if you don't ever want a leak there again, and you don't need the speedometer drive, remove it, and fabricated a plug with an o-ring that fits into the housing socket and call it a day. You can also gut the speedo drive, weld the center of it shut (where the pinion shaft used to fit), and install with a new outer o-ring.

Edited November 9, 2011 by cygnusx1

[mlobster]

Thanks guys! I have no current issues with leakage from the speedometer connection to the transmission. I appreciate the very helpful inputs, except for the first reply =x. Btw thw reasom i am going with the speedhut gps speedometer is because of the technology, it's other features like 0-60 time, 1/4 mile time, current direction, etc. Plus it is easy to use, no calibration needed, no speedometer cable to worry about. There are some downsides but very minor, such as it won' t function going through tunnels, etc. Anyway, if i am the only one using a gps speedometer then i highly encourage you guys to check them out. Anyway, i appreciate the help once again.

[cygnusx1]

Sounds like a fun tool. I have often wondered if GPS units for cars, compensate speed for incline and decline. I have found that the GPS windshield nav units always read low when going up or down steep hills, as compared to ground speed (analog speedometer). Sin Cos Tan is the reason. Any engineers know if they are corrected from horizontal speed?

[Fire604]

Yeah, I just ordered one too the other day. My speedo is off significantly because of the wheel/tire change and I figured this would be easier than trying to change out the speedo gear since I plan on another tire size change in the future. I was swapping out other gauges anyway so I figured this was the best option.

If anyone else is using one I'd like to hear your impressions on how well it has actually worked out for you.

[mlobster]

Gary in NJ, I guess I wont be the only one using a GPS speedometer . Yeah GPS sounds a lot more practical other than the fact that you may lose signal in certain conditions. I too am swapping out all of my gauges. My first priority on my car is to change out all the electrical wiring with a new harness, and since my dash is out, might as well change out the gauges.

[ktm]

Ron Tyler at Hybridz installed one about 6 months ago or so (IIRC) in his (former) M3 swapped 260z. He loved the functionality of the GPS speedo. It does save a lot of headaches, but then again creates a few (such as odometer and tripmeter readings.....).