Took truck out for spin yesterday since weather was above freezing; played around with speedo. I have cable connected to the AOD and it spins so I re-connected it to my dash mounted speedo (mid '80s F150).....didn't work but I think that was because I didn't have cable meshed properly with speedo.

Tried the original speedometer (50) connected to the cable but it wound it out to maximum scale and then started to whine. I was hoping to possibly use the original speedo but looks like this won't be the case.

Will have to put more effort into this when it warms up ! Think May

Tom

 

Tom, have you done any research to determine the speedo gear ratio your original trans may have used? Sounds like you are way off with the AOD, but they do make external reduction units. Working original style guages are cool. I'd do some reseach. Somebody on this forum could help. I bet number dummy can recite gear tooth count options for you.

 

Tom,

Wow, winter progress....good for you

If the cable was spinning it should work the speedo head (might not be the right ratio) but it should move the needle. My guess would be that the cable is not meshing into the speedo head properly. Maybe the cable isn't going deep enough into the head or something like that.
If the cable housing connects to the speedo head then it might just be a matter of getting a new universal cut to length replacement cable and fit it as necessary.

Good luck
Bobby

 

Thanks for the responses, I haven't looked at the gear ratio aspect as of yet. I think the '80's speedo ratio should be close to the AOD out of my '90 Crown Vic but connection under dash is very tight, so I will exhaust the connection issue first.

I'll do research on the gear teeth of the AOD; it is unlikely the stock speedo is going to match. It would move the needle when connected to the cable, but pinned it so I disconnected it.

Too "fresh" in the garage to play with truck issues, back to work today for two weeks so porbably won't fix 'til spring.

It was nice to cruise Friday, always good for the spirit to drive the old truck.

Tom

Tom

 

I looked into info on the AOD speedo gear, stock should have been 8 teeth
Based on my 3:73 rear ratio; wheel height of 26" recommended gear is 22 teeth ? so.............what's involved in changing the tranny speedo gear?

Tom

 

Tom,
I've mever messed with an AOD but I've toysed with several other styles of trannys.

So it kind of depends on if you are needing to change the "drive" or the "driven" gear. The "driven' gear is easy. Just pull the speedo gear housing out of the side of the trans and swap the gear out. If its the "drive" gear you'll probably have to pull the tailshaft housing off to get to it.

Bobby

 

Thanks Bobby;

Looks like the second (easier) option would be to go with an external cable in-line converter.

I have a "heavy" down gearing issue with my AOD; it downshifts pretty "dramatically" into low range when I slow down and hit the brakes. Will probably have transmission shop look into adjustment if possible and install converter at the same time. Not into pulling tailshaft off tranny layinig in my driveway.

Tom

 

Tom,
Again, I'm not too familiar with the AOD's
I'd get it adjusted as soon as possible, if its anything like some of the GM trannys it doesnt take long driving with them out of whack to screw things up (the ones with the TV cable)

The tailshaft housing isn't as scary as it sounds. You pull the driveshaft, typically 4 bolts hold the housing on. You slip it off and then a "C" clip holds the "drive" gear to the shaft.....again, I'm just guessing on this.

I'm with you though, laying out in the driveway messing with ATF dripping down your arms just doesnt sound very appealing.

Sometimes you can get lucky and find those in-line converters at the wrecking yard. GM used them quite a bit throughout the 1980's

Bobby

 

The drive gear on the AOD is cut directly into the output shaft. It's either 7 or 8 teeth.

To change the driven gear is very simple. Just unbolt the cable from tailhousing, remove C clip on end, slide gear off and new one on, reinstall c clip.

New gears are like $10 each.

 

Not really off-topic, but the AOD does have a TV cable, and if not adjusted properly it can wreak havoc. Definitely get that looked at sooner than later.