Speedometer Correction

[DadTruck]

I have picked up a gage cluster with gages instead of idiot lights.
Prior to swapping it in, I would like to get the speedometer gearing adjusted to match up to the tire size that is now on the truck. Anyone recommend a store / site that does this?

thanks

[75 Power Wagon]

I went down to the local Napa Auto Parts store.. and they had a source that makes the speedometer cable drive gear reduction box.. They had me figure out the reduction ratio by driving 1 mile in an accurate car, and getting the reading from the truck.

I believe the outfit that they ordered the part from was out of Sacramento, CA.

I'm not sure where you are located, but i would go talk to your local parts store.

[Speed Dragon]

You just change the speedo gear in the trans mission, take the cable loose, there's one bolt in a clamp (it looks like a distributor clamp) take it out, and the speedo gear assembly pulls out.

[bherder]

This is what I used to figure out what gear I needed..

http://www.mymopar.com/speedometer.htm

I have 33" tires on my truck, so I had to do a little ratio computation ... My buddy buck was kind enough to send me a gear for Xmas :D ....

I got it installed and went into town where I knew that they had one of those road-side "Your Speed Is XX" radar things .... and my speedo was damn near dead on. At 45 mph it was about 1/2 mph off, and I can live with that ;)

[DadTruck]

the truck has an A-833 manual,, does the one bolt removal to access the tranny spedo gear apply? or was that for automatics

thanks

[B-300]

An 833 manual has the same 1 bolt gear holder/cable connection as an automatic. I have almost every gear tooth count made as I have run almost every axle ratio made in the past.... For 27.4" tires I found that a gear just less than the axle ratio was correct.
Example: A 3.55 needed a 35 tooth gear.

[DadTruck]

the truck has a 3:21 axel ratio, with 28 inch diameter tires it should take a 2838931(green) trans speedo pinion, have found that part was discontinued, and replaced by the 52068153,which has also been discontinued.
any thoughts on where to get one of these? If someone has one they would consider selling, let me know.

thanks

[C1DoG]

went into town where I knew that they had one of those road-side "Your Speed Is XX" radar things .... and my speedo was damn near dead on. At 45 mph it was about 1/2 mph off, and I can live with that ;)

That is exactly how I figured out my speedometer... The previous owner has the speedometer set on Kilometers instead of Miles :crazy:

[CaseyMoparRoss]

what causes the speedometer needle to bounce out of control?

[3834B]

what causes the speedometer needle to bounce out of control?

Usually a binding cable.

[bherder]

the truck has a 3:21 axel ratio, with 28 inch diameter tires it should take a 2838931(green) trans speedo pinion, have found that part was discontinued, and replaced by the 52068153,which has also been discontinued.
any thoughts on where to get one of these? If someone has one they would consider selling, let me know.

thanks

Mmmmm .... Have you tried googleing up something like 'Speedometer repair parts' ... Something like that? There's got to be places that do speedo/gauge repair and calibration... I would think that a business that does this sort of work might have, or know where to find gears..

[DadTruck]

Thanks,,I have found shops that can re-calibrate the speedometer, lwas looking for more of a "factory" fix. I did not think to ask to see if they had any trans pinion gears, thats an idea

on the bouncing needle, yep, dry speedometer cable, on my 83 I removed the gage cluster, freed the speedometer cable at the cluster and trans end, ran motorcycle cable lube through it till it ran out the trans end, has been fine for over a year now.

[cribbs74]

Brewers Performance(Google) has the speedo gear for your 833. 70 bucks new and about 20 for a good used. I bought a used one from them for my 833 and it looked and works like new.

[DadTruck]

cool

thanks , I'll look there