Help with Speed Sensor Gear
Thread Starter
8th Gear
Joined: Oct 2009
Posts: 8
Likes: 0
Help with Speed Sensor Gear
My speedometer crapped out the other day on my '85 on my way home. I removed the speed sensor and the center of the plastic gear had a groove worn in it. After searching the internet and calling a few trans shop I found a used 42 tooth gear and it didn't match exactly to the old one. The inside of the cone had a raise lip that I will have to grind down to make it work. Is there a reason it is so hard to find a gear for the 700R4 that exactly matches. Also my speedometer is off, when it reads 40mph I'm really going 43-44mph. The guy at the trans shop said I need to find a gear with less teeth, Is that true? Any help on this matter would be greatly appreciated.
Drifting
Joined: May 2013
Posts: 1,736
Likes: 31
From: Reno Nevada
Team Owner
Joined: Sep 2003
Posts: 25,348
Likes: 2,728
My speedometer crapped out the other day on my '85 on my way home. I removed the speed sensor and the center of the plastic gear had a groove worn in it. After searching the internet and calling a few trans shop I found a used 42 tooth gear and it didn't match exactly to the old one. The inside of the cone had a raise lip that I will have to grind down to make it work. Is there a reason it is so hard to find a gear for the 700R4 that exactly matches. Also my speedometer is off, when it reads 40mph I'm really going 43-44mph. The guy at the trans shop said I need to find a gear with less teeth, Is that true? Any help on this matter would be greatly appreciated.
Once the speedometer is actually working again then it would easier to help you if you could post your speedometers reading when doing 45 mph, 50 mph, 60 mph, 70 mph with a GPS. We need to establish a % of error to be able to correct it.
I wouldn't worry about vendors until you understand the damage to what you have. Have you changed the rear axle gears? Was it changed before you? The more information you can supply the easier it will be to help you.
What color is your VSS? White or black are your choices!
