T5 Swap Complete - Speedometer is jumping

[95BlackTan50]

After two long days, the AODE is out and the T5 is in. All is well except that the speedometer jumps around a lot at speeds above 50 mph. I've tried taking the Speedcal in and out and switched from the new T5 speedo gear to the old AODE speedo gear after trimming it down to size. All of the above combinations give the same results.

Anybody see anything like this before?

 

[urban96]

new VSS sensor?

 

[95BlackTan50]

new VSS sensor?

Could be. It just seems odd that it would be good with the AODE and bad with the T5. They're not too expensive so it might be worth a shot.

 

[NotQuik]

Just out of curiousity where did you get your pedals, computer, and tranny harness from? I ask because i'm fixing to do hte same thing with mine and i'm in the process of collecting parts right now.

 

[95BlackTan50]

Just out of curiousity where did you get your pedals, computer, and tranny harness from? I ask because i'm fixing to do hte same thing with mine and i'm in the process of collecting parts right now.

I got most of my parts from a salvage yard in Northeast Tennessee called Performance Parts & Sales. Nice people to work with. I dealt with Michael mostly and he was very helpful.

http://www.performancemustangparts.com

 

[final5-0]

After two long days, the AODE is out and the T5 is in. All is well except that the speedometer jumps around a lot at speeds above 50 mph. I've tried taking the Speedcal in and out and switched from the new T5 speedo gear to the old AODE speedo gear after trimming it down to size. All of the above combinations give the same results.

Anybody see anything like this before?

Hey Barney

Not sure about the trimming down of the gear thing

but

have you tried the correct or unmodified gear as opposed to your modded aode gear?

For 373's, IIRC, you can be close with a 23 tooth driven gear.

Grady

 

[95BlackTan50]

Hey Grady,

I started out with the red 21 tooth gear for the T5 which was supposed to be correct for 3. 73's with a 7 tooth drive gear. I only tried the old 18 tooth AODE gear with the trimmed shaft after the speedo exhibited the jumpiness with the 21 tooth gear. I read somewhere that if you use the speed cal that you should use the original speedo gear since you supposedly get better gear meshing with less teeth. In any case, I got about the same results with both speedo gears.

I picked up a VSS at lunchtime today so I'll try that tonight. It was cheap and will be easy to swap. If that doesn't work I'll try to modify my AODE tranny cable to swap that in to see if it helps. The T5 tranny cable that I got was pretty beat up so it could be intermittent or something. I will probably clean all the connections first and put on some dielectric grease just to triple check that I have good connections before I modify the AODE cable.

Barney

 

[urban96]

im using the stock trimmed AODE gear with my T5 right now and its working fine


double check all your connections, maybe use some electronic grease on them... if it still does it try a new VSS. 50resto has then for around $20 i belive

 

[95BlackTan50]

I replaced the VSS and did some serious cleaning on all of the connections. Still the same jitter on the speedometer. I think that leaves the tranny cable (electrical) or drive/driven gear slipping (mechanical). I think I'll wait until the weekend to try anything else.

 

[95BlackTan50]

Update - I pulled the SpeedCal back out and put in a 23 tooth speedo gear. The speedometer still bounces around by a couple of MPH but the motion is pretty smooth. I think that the drive gear of the used/rebuilt tranny must be worn because the bouncing is too regular to be an intermittent electrical problem. I think that the SpeedCal made the response worse since it must be expecting a clean input signal.

The big difference between having the 23 tooth speedo gear with no Speed Cal and the 18 tooth gear with the speed cal is that with the Speed Cal removed, the smooth variation of the speedometer allowed the cruise control to work properly. With the Speed Cal, the cruise control had a hard time detecting the true speed.

I don't think that there is anything wrong with the Speed Cal since it worked great for me for a year before I did the tranny swap. I don't think it could handle the variation that I think the speedo drive gear is causing.

 

[final5-0]

Update - I pulled the SpeedCal back out and put in a 23 tooth speedo gear. The speedometer still bounces around by a couple of MPH but the motion is pretty smooth. I think that the drive gear of the used/rebuilt tranny must be worn because the bouncing is too regular to be an intermittent electrical problem. I think that the SpeedCal made the response worse since it must be expecting a clean input signal.

The big difference between having the 23 tooth speedo gear with no Speed Cal and the 18 tooth gear with the speed cal is that with the Speed Cal removed, the smooth variation of the speedometer allowed the cruise control to work properly. With the Speed Cal, the cruise control had a hard time detecting the true speed.

I don't think that there is anything wrong with the Speed Cal since it worked great for me for a year before I did the tranny swap. I don't think it could handle the variation that I think the speedo drive gear is causing.

What a bummer if you gotta go into the trans

If you do, you can install the correct drive gear and the speedo will be right on the money

Good luck with it Barney

Grady

 

[mr.p]

Okay, similiar problem here with a slight twist. T5 tranny with 140 speedometer. The speedometer bounce once I reach 50-60 mph, but the odometer stays correct (the tenths are going by at a normal steady pace). Once you get back below 50 it acts normally. The speedo gear in the tranny looks good, I'm thinking that since it works fine a slower speeds it might be the speedometer.

Ideas?

Thanks

 

[95BlackTan50]

T5 Swap Complete - Speedometer is Jumping - *Finally Fixed*

Hey all,

After a year of dealing with a noisy, uncalibrated speedometer I finally dropped the tranny and took off the tail extension to see what was going on. Turns out that the drive gear was not properly seated on the spring clip. The un-notched part of the drive gear was sitting on the clip giving the gear a bump which was creating a bad interface with the driven gear. You could actually feel the bump by sticking your finger in the VSS hole and rotating the output shaft.

The good news is that it gave me a chance to put in the 7-tooth gear that was supposed to be in there in the first place but wasn't. Anyone need a slightly used SpeedCal?

It only took about an hour to swap the gear once the tranny was out. I was suprised how easy it was to change. Now that the tranny is down, it's time to fix the rear main seal leak and find my vibration broblem!

Barney

 

[reddy351]

Anyone need a slightly used SpeedCal?

What are you asking for it? I'll be going to 4.10's soon and may need it.