Speedometer problem

[ox_ford_guy]

Jarendall..Thanks, I will give the calculator a try.....ox_ford_guy

[ox_ford_guy]

Rallysnake..Got the new speedo gears in the mail today. Will install in a few days and let you know how I make out. Also, how did you couple the 2 ends of the speedo cables together to make a longer cable with a more gradual bend?......ox_ford_guy

[RallySnake]

Oxford,

My Arntz only has about 3 inches between the back of the speedometer and the fiberglass firewall. I have tried 90 degree connectors and flexible cables, but they never work very long and the needle tends to fluctuate a lot. I could not find a single cable long enough, so I joined two together to make an extra long cable. This is the way I did it:

1. I found a short length of tough plastic tubing that had an inside diameter smaller than the outside diameter of the two cable ends.
2. After carefully measuring the lengths of the cables and housings, I drilled each end of the tube to precisely fit the metal sleeve on each of the two cables with the right amount of drive cable projecting out of the far ends.
3. I drilled a 1/8" hole in the center of the plastic tube.
4. I cut a few lengthwise slots about a 1/2 inch long in each end of the tube to allow it to compress.
5. I cleaned the inside of the tube.
6. I found an electrical crimp-on connector that fit tightly on the square ends of the drive cables.
7. I removed the plastic insulator from the crimp-on connector.
8. I greased each cable with Slick 50 grease.
9. I slid one end of the first speedometer cable through the plastic tube and then crimped the two drive cables together.
10. I mixed high strength epoxy and applied it to the outside of the metal sleeves on the ends of the two cables to be joined.
11. I pushed the two cables into the plastic tubing and clamped them in place with heater hose clamps over the cut ends making sure that epoxy was sealing all the cuts.
12. I put the assembly under a hot light bulb to give the epoxy extra strength and left it for 24 hours.
13. I installed the cable. It is now long enough to pass straight through the firewall, over the right bank of the engine, loop around over the passenger footbox, drop down across the back of the engine, curve back over the transmission, loop down along the bottom of the driver's side of the transmission and up into the tailshaft housing.
14. I used a bunch of cable ties to hold the assembly in place and kept the bends as gradual as I could.
15. I sprayed a little Triflow lube into the hole in the middle of the plastic tube then sealed it up.

Works great and the speedometer needle doesn't even fluctuate!

Paul

[Lowell W]

Now THAT is pretty dang clever!

Auto parts stores sell (or used to, anyway) universal cut-to-fit drive cables with a crimp on end and a little crimping tool. That would allow you to R&R the drive cable without having to dismantle your outer cable, if you could buy one long enough.

Great idea!

Lowell

[ox_ford_guy]

Rallysnake...

Hats off to you..Thats really determination to solve a problem. Quite a process you came up with. I printed it out and will give it a try..Thanks..0x_ford_guy

[ox_ford_guy]

Rallysnake/Jarendall/anyone else..

I Took out the speedo cable again today. Existing black 20 tooth gear o.d was the same dimensionally as the new ones I purchased. However, I greased eveything up real well including the reverse mechanisim on the speedo, put on the new gear and carefully re-ran the cable.
No luck..Still not working.

I tried runnning the speedo with an electric drill from the trans end and it worked very well with no jumping or any other abnormal behavior.

I took off the speedo end of the cable and the cable turns while the other end is in the trans. This can't be right. Should be locked.

Ran the car with speedo end off and trans end connected into trans and found cable does not rotate inside sheath at speedo end.

I also reconnected the cable and ran it with the rear wheels still off the ground just to cover all bases. Still nothing.

Either the Tremec uses a special speedo gear or somthing is not engaging in the trans, although the speedo did work for the first 150 miles when I got the car.

Some more confusion also because John's Mustang shows 2 different gears depending on the year of the trans and my rear ratio (3.55) 23 teeth(white) for 90-98 trans or 20 teeth (black) for 83-89 trans with 3.55 rear.

The 23 tooth would be a little bigger in diameter. Maybe thats it?If I tried the 23 tooth might I damage anything further?

How does one know which trans year he actually has? (I was assuming 83-89 because the gear that was in the car was black and Rockland originally told me last time I called the trans was a 83-93 version)

Going to call Rockland Standard Gear again tommorow to try to get some solid tech. support.

Any other ideas from anyone would be appreciated before I go crazy and pull the trans for repair..Thanks ...getting desperate....ox_ford_guy

[jarendall]

if you have a pre 96 T5 it is a borg-warner, the different size gears are for the different geared rearends and tire height, any of the T5 gears should work and not make a difference in connecting to the drive gear, sounds like you do have a issue with the drive gear, the T5 is a very complicated transmission, you may need to see a good transmission guy

[Ron61]

If your gear that you bought and put into the transmission end isn't showing any sign of wear or even of the teeth of the drive gear touching it, then it almost has to be a problem with the drive gear in the transmission. I don't know how hard yours is to get to, but can you take a light and look inside the hole where the cable and gear goes and see your drive gear? As said above, unless you are a good transmission person, it would be best if the drive gear is the problem to take it to a transmission shop to have them replace it. Also you said with then old gear it just started jumping around. Have you tried putting the old gear back in and seeing if you get any resistance or it will turn at all?

Ron

[ox_ford_guy]

JARENDALL/RON61

Thanks for your replies. I have tried everything and I also believe it has to be a drive gear issue inside the trans.
Through tag number, the yellow (7 tooth) speedo drive gear inside and the gearing ratios, I can tell it is a recent model T5 World Class trans. Although out of warranty now, the trans only has a few hundred miles on it.

I have tried reinstalling the original and new speedo cable gears and cables with no positive results. Still no resisance when turnrd manually from the speedometer end.

Before your messages, I had taken a small dental mirrior and looked up in the cable hole. Through the hole (out the side of the cable hole) I can see about 2 of the spirial teeth on the yellow (7 tooth) inside gear. The gear has teeth on it and basically looked ok. However, because of the limited viewing potential, I could not really tell with high confidence if damaged to any degree.

I rotated the rear wheels and the yellow gear did turn with the trans output shaft. Also tried to verify the gear material but could not because of the poor access.
Looked really well again and still could not find any trace of damaged gear material of any kind anywhere in the cable mount hole or on any gears.

I did notice that the yellow (7 tooth) speedo gear inside was off to the side of the hole I was looking through, with only the first 2 spirial teeth showing.

I am wondering if this is right or should the gear be centered more with the hole?

As I mentioned previously, the speedo did work for the first 150 miles.
This is a real longshot but if the yellow speedo gear is supposed to be centered, maybe the gear moved over somehow inside the trans and is no longer making proper contact with the cable gear. Thus no notable damage to either gear.
Although this gear is supposed to be retained by a clip, maybe it somehow slipped out of position or the trans was mis-assembled without the clip in place.

I tried to contact Rockland Standard Gear's tech line (2 times) for some guidance with no call back so far....What do you guys think..Open to all suggestions from anyone..Thanks..ox_ford_guy

[davidlee]

ox ford guy
I had the some problem on a non-cobra car{speedo worked with a drill hooked to the plastc gear but not when hooked up to the tranny} Come to find out the speedo cable {the inner one} was just enough too short when it was hooked up to the tranny the bend in the cable made the inner cable not quite long enough to mate into the plastic speedo gear. I bet I took the ---thing apart ten times and could not figure out the problem. Finally I figured it out. In my case the part that goes into the tailshaft of the tranny had two cable adaptors {a short piece of cable with a male and a female end on each one} so all I did was to put a spacer in between the adaptors to lengthen the cable. Problem solved. I don't remember if my Cobra had any adaptors but you accomplish the same thing by shortening the cable housing just a tad.
Hope this helps

David

[Ron61]

David,

Just a question. When you were fighting with yours, did you try putting the gear in the transmission and turning it with the cable disconnected from the speedometer? It seems that when ox_ford_guy does this with his, it just turns freely which would indicate it is not meshing with the gear in the tranny as he shouldn't be able to turn it at all. And with it not connected to the speedometer, he should have plenty of slack to get it seated all the way down in there.

Ron

[davidlee]

Ron61
No, the head of the speedo was just too difficult to get to. I did disconnect the cable from the gear housing at the tranny and the short cable adaptors/extenders would only rotate when the drive shaft was rotating. You could not rotate them at all, ie the speedo gear was meshing with the tailshaft gear

[Ron61]

David,

Thanks for the answer. I had an older car once like that and couldn't hardly get to the back of the speedometer at all so I just took a universal cable which back then didn't cost hardly anything and cut it into a short piece which I put the driven gear on and then stuck it into the transmission to test my gear in there. Of course in my case it was on the speedometer end and I worked two days getting that darn thing out. I have a shop manual on these transmissions and a CD that shows how to tear them down and where every piece goes, but I am not at all mechanically inclined and would take mine to a transmission shop before I took it all to pieces. I can't even look at all of those pages of exploded pictures and tell which gear goes where and some springs have to be held in place and on and on.

Ron

[ox_ford_guy]

Davidlee/Ron61..This sounds possible. Thanks for the reply. This is why I think these threads are invaluable....There is a "retainer bushing " at the speedo end of the cable that might possibly be limiting travel of the inner cable all the way into the trans, when all is totally assembled.

I have tried operation with the cable disconnected at the speedo end but maybe there is still not enought inner cable with bends. etc. I will definitely give this a second look ..Thanks..ox_ford-guy

[RallySnake]

Oxford Guy,

Years ago I rebuilt a Muncie 4 speed transmission. I was not careful when I reinstalled the speedometer drive gear and pushed it too far down the tailshaft. I had exactly the problem you are describing. The drive gear SHOULD be centered on the hole. If it's possible to pull the tailshaft housing off while the trans is in the car, it could be an easy fix. Most Cobra's don't have room for that, though.

Or, you could buy an electronic speedometer and drive a sensor with two magnets on the u-joint?

Paul

[jarendall]

are you sure you have a T5, Borg-Warner sold out to Tremec in the middle 90's, I think they kept making them for a couple more years, I don't know if the Tremac took a different driven gear, you may have a different Tremec transmission altogather

I have done some research on the T5, Tremec still makes the T5 for the V6 Mustangs, the drive gear and the driven gear are still the same as the old Borg-Warner, the newer ones have electronic sending units instead of drive cables, I have found an interesting article on the T5 check it out:
http://www.ffcobra.com/FAQ/speedo.html

[ox_ford_guy]

Rallysnake/Jarendall....Yellow 7 tooth inside drive gear is definitely off to the side of the hole and not centered. Must be the issue and it will most likely have to go to a trans shop.

I am sure it is a T5 as the tag number of my trans 1352- 251 07455 jibes with that shown for the T5 Z on the Forte's parts connection website (www.fortesparts.com)

The Rockland Standard gear invoice that came with the car lists the trans gearing as 1st=2.95/OD=.63. this gearing is consistant with T5 world class specs and along with the yellow 7 tooth speedo gear inside all point to it being a T5 world class. (Also, the car was advertised by the previous owner as having a Tremec T-5 when I purchased it.)

However, I have been looking into the electronic solutions also. As my Backdraft has a speed sensor pickup in it's BMW rear end, I my get lucky.

I found an electronic (little black box) product on-line called Cablex (www.gaugeguys.com) that will pick up an electronic speedo signal and convert it over to drive a mechanical speedometer. A little steep at $295.00 but would eliminate tricky cable runs, cable binding. etc. and more possible problems later. Might prove to be a good solution for others in the future.

I may also use the same approach but with an electronic speedo only, but only if I can find one that matches my other Autometer gauges. I'm wondering,does anyone know if Autometer makes a eletronic speedo that matches with the original mechanical type in looks?
Have to compare costs of tranny pull and gear fix vs the electronic solutions.

Also, I looked at the link regarding speedo gearing, etc found it very interesting......Thanks again to all..ox_ford_guy

[RallySnake]

Oxford Guy,

So, there's no hope of pulling the tailshaft housing off under the car?

Paul

[ox_ford_guy]

Rallysnake...Maybe..But can't attempt right now as I am getting the car prepared to ship to Florida for the winter late next week. Have to look at it there, but not reaaly confident I have the knowhow or can do it on the garage floor..Getting too old for that stuff. My have to go to a shop if I go the mechanical way..Thanks...ox_ford_guy

[Ron61]

Oxfordguy,

Enjoy Florida and I hope the transmission turns out to be a simple thing. I like the way mine is mounted. I can take it out from under the car and I have timed it twice and from the moment I started taking the shift handle off until I had it on the bench was just 20 minutes. But even with the manual and CD showing every spring, bolt, and nut, I would not tear into it as I am just not mechanically inclined at all and would just wind up paying extra to have a transmission shop fix what I had lost or messed up on top of the original problem.

Good Luck and Best Wishes,

Ron