I need to replace the speedometer gear in my transmission. But I can't find a replacement. Does anyone have any ideas where I might find one of these?

 

best bet would probaly be the local junk yard

 

Becoming a j/y only item. GM has quit making a good deal of the drive and driven gears. You might luck out and find a tranny shop that has some in stock and willing to sell. If its a 4x4 make sure your getting the reverse roatation gears as the 4x4 and 2x use different gears (both drive and driven. I just had the same problem not a few months back and wound up cutting my drive gear (the one in the tranny) in half and moving the peices around so good teeth were on the driven gear (one the speedo cable attaches to).

You might wanna make sure the metal peice the driven gear sets in is steel and not alumunim, the AL ones are bad about wearing out and allowing the gears to have slack in them making them strip out.

 

what year is your truck?

My local GM dealer carries the old style speedo gears, and so do most tranny shops, especially speed shops. Teh 700R4 is still in use in lots of different applications. Google Raptor 700R4 and you will come up with a site that sells everything you need and then some. Scroll down the page, they got everything to rebuild trannies, including the speedo gears. Check Summit racing as well. Buy new, they are like $10 each.

 

For a 2x, in the 4x they are located in the transfer case and was a dealer only item. The 4x4s use a reverse rotation gears and the ones from a 2x will not swap out.


I really wish you can prove me wrong and an idiot cause I looked for 2 months before I jerry rigged mine. Its still working but I'd really like to fix it right. Its a silver 20 tooth driven and a tan (if I recall) 17 tooth drive that my 87 takes. Fits inside on the drivers side of the 207 NP transfer case.

 

http://www.transmissioncenter.net/SPEEDO-17T.jpg

http://www.transmissioncenter.net/highperf700r4.htm

about 3/4 the way down hte page.

NP208 t-case gear
http://www.transmissioncenter.net/HPIM1465.JPG


I bought mine from the dealer.I bought it for a '87 S10-Blazer. put bigger tires on it and needed a new speedo gear, dealer had it in stock. There are web sites that still sell them.

By the way, '87 was the last year for the mechanical speedo in the S10-Blazers. '88 they went to a electronic version, and later on they went to a reluctor ring, like in '93 I believe, when the 4L60e came out in the S10-Blazers.

Not saying your an idiot,we all gotta learn sometime.

 

Won't work in mine, the gear is different. I tried a 208 gear. I called a couple of tranny shops within a 2 hour distance and had them looking at every possible soulution. I was almost to the point of going to a autometer dash before I was told how to jerry rig it.