Nothing of what I am useing is from the Diff I unbolted it from side of transmission just like on a gasser but this is set up for electronic speedo like I said Tomorrow I will take a picture of the complete unit that I pulled apart to make what I needed for my crewcab . the first donor was a 3500 srw reg cab the second truck was a Drw reg cab both truck's were Auto .

 

Ill plan to take mine off this afternoon, i have hay to get out of field & covered before Sandy showers come, if they do. Thanx again for your troubles.

 

THIS style of VSS is used on the following applications;
1990-1993 2 WHEEL DRIVE WITH manual transmission.
1990-1993 4 WHEEL DRIVE with manual or auto (mounts at transfer case w/ratio modifier).


In the FIRST GEN TRUCKS, THIS style of VSS, WHICH USES A THREE WIRE PLUG, is used on the 1991-1/2 through 1993 2WD AUTOMATIC, NON-OVERDRIVE (A-518) application ONLY:


With respect to adapting the VSS to either the transfer case, or the 2WD transmissions, the pic below represents the speedo adapting pieces for 4WD with the NP205 (LEFT) and the 2WD version (RIGHT).
1990 through 1993 absolutely did NOT use an axle sensor to read vehicle speed!!!



Reading the speed off the axle sensor didn't start on Dodge Pick-ups until 1998!
Prior to that, all speed was read and counted off of the methods outlined above.

Mark.

 

I just took my vss off, it looks like the top pic on left but the pic on right appears to be what is remaining in tailshaft. I plugged electrical connection to the VSS/turned ign on & attached a drill to the square stem protruding from the VSS, thinking i would get a reading on speedometer and i did on both. Should i pull the remainder of shaft/gear from tailshaft (im do have some leakage) to inspect gear & replace seal or what should be my next move?

 

Mark, thanks for clearing that up!! Learn somethign new all the time here..


Necred,
inspect the VSS, look forrounded off edges on teh square shaft, and sorrosion on teh conncetors.
The VSS is the most common part to fail.
the next most common would be worn teeth on the pimion gear, or rounding off of teh sleeve teh VSS shaft slips into.
It can be inspected by removing the clamp holding it, one bolt, and it should simply slide out. you can then get a finger in there and feel for worn orbroken teeth on the worm gear.

My money would be on the VSS being the issue tho since that is the ussual culprit

 

Is there no way of testing VSS? The old one did have a slight rounded edge, however both reacted the same with the drill test. I may replace the seal & oring anyway on pinon shaft, do you happen to have a PN for either?

 

Fixed speedo with VSS....Ok, i found large gear broken, does smaller gear have teeth missing from factory? My circuit board has discoloration on left, is this a concern? can CB be purchase? I hate to order gears if i need a cb..I tried to upload pics....

 

E mail me some pictures I will post them for you simplysmn@aol.com

Val

 

Thanx OTW.

 

OK Hope this help's so we can help you figure out what's wrong

 

Thanx Val,
What your opinion on "mold"? I believe there is a coating over the CB & maybe thi smold is under it. Is the small gear broken or is it made with space? I saw another pic online with their small gear having missing teeth, although i didnt find any in the housing.

 

I've never had the back of a speedo apart I would say Clean it off with rubbing alcohol

 

You need both gears. I would give it a try with the cb and see if it works.

 

I appreciate yalls input, i will follow up.

 

Don't mean to hijack, but dumb question.... what does VSS stand for?
And, just to be clear a bad VSS will cause odometer to quit working, but the speedometer keeps working? That's the issue I've got and I thought it was the odometer gears behind the gauge. So, this may be good news for me.