Speedometer help

[OJOE]

put a 93 1500 350 auto together out of spare parts. now when the truck speedo points at 50 mph my gps says 60mph. talked to gm parts said i need tire size and rear gear and they would sell me a buffer for the speedo to correct this for about 170.00. anyone know a cheeper fix

[OJOE]

Originally Posted by OJOE

put a 93 1500 350 auto together out of spare parts. now when the truck speedo points at 50 mph my gps says 60mph. talked to gm parts said i need tire size and rear gear and they would sell me a buffer for the speedo to correct this for about 170.00. anyone know a cheeper fix

sorry, maybe one of the mods will move this over to the 88-98 side. thanks joe

[trkklr77]

well its a vss sensor truck for starters, you might be able to adjust it by playing with the speedo drive gear in the tranny, if they even have them.

[OJOE]

Originally Posted by trkklr77

well its a vss sensor truck for starters, you might be able to adjust it by playing with the speedo drive gear in the tranny, if they even have them.

what is a vss sensor? and there is no speedo drive gear in the trans, only a electronic p/u. i am kinda dumb on this, can you explain how to adjust this vss sensor. thanks

[Mickey_D]

Didn't 93 use the DRAC? If so, you can take them apart and change the jumper settings.

Info here : clicky link

[OJOE]

Originally Posted by Mickey_D

Didn't 93 use the DRAC? If so, you can take them apart and change the jumper settings.

Info here : clicky link

you are correct and thanks for the link, very helpfull info

[Hart_Rod]

Joe,

I had a 91 motor/tranny combo in my 34 Ford. It was a 305 TBI with a 700R4. The tranny had a VSS to provide input to the computer. But it also had the plastic gears in it that you could change to correct for speedometer. Here's a chart with the different gears:

http://www.transmissioncenter.net/sp...n_______va.htm

http://www.tciauto.com/Products/Comp...eter_gears.asp

http://www.enginebalancers.com/Produ...eedo_gears.asp

http://www.thirdgen.org/speedogear

Dakota Digital also make this:

http://www.dakotadigital.com/index.c...rod/prd126.htm

Instructions:

http://67-72chevytrucks.com/vboard/s...d.php?t=243548

[OJOE]

thanks rod, but mine does not have a gear, only has a magnetic pick up on trans

[trkklr77]

Originally Posted by OJOE

what is a vss sensor? and there is no speedo drive gear in the trans, only a electronic p/u. i am kinda dumb on this, can you explain how to adjust this vss sensor. thanks

uh that would be a vehicle speed sensor.

[OJOE]

Originally Posted by trkklr77

uh that would be a vehicle speed sensor.

maybe, vssb, vehicle speed sensor buffer (uh) anyway thanks for the great help!

[trkklr77]

Originally Posted by trkklr77

well its a vss sensor truck for starters, you might be able to adjust it by playing with the speedo drive gear in the tranny, if they even have them.

Originally Posted by OJOE

maybe, vssb, vehicle speed sensor buffer (uh) anyway thanks for the great help!

that is the vss, aparently they are not the same drive system as i had hoped. you will need the buffer OR you can adjust the computer on some systems. odb1 you might not be able to but odb2 deffinetly. you will need to get something like a power programer to do it.