speedo gears

if i change the rear gears where would i get the right speedo gear so the speedometer reads atleast half a$$ right if not correct.  
color dont matter when it passes

Check out this site:  

http://www.transmissioncenter.org/GM_Speedometer_Gears.htm

they have all kinds of speedo gears.  I been needing to get some new ones for my 200r4 in my truck.  

The 200r4 came out of a wagon with a 2.28 axle and now its in a truck with a 3.73 axle  it reads about 80 when your actually going 60.  

After the post here last week I contacted TCI. My 200R4 runs about 10% fast also. TCI desn't carry the gears for 200R-4s anymore but there are others that do. Good luck..  

This chart might also be helpful:  http://www.montess.org/speedo_gears.html  

I aint sure this guy has a 200r4 trans I was just adding my 2 cents on speedo calibration.   He didnt mention what trans or gears he has.  

Righto, yep I realized that after the post.    

almost all speedometer shops have ratio change boxes they can install right at the transmission speedo adaptor and then the cable to the other side ..   they have various gear sets inside..




a huge trick...  when junk yarding..   find 79 to 85 eldorados...  and 80 to 85 flat back sevilles.. along with tornandos and riverias..  from 79 to 85.. with the normal direction front to rear motor and the front wheel drive..

there is a speedo cable adaptor down on the transmission and hard to remove.. that has a 90 degree bend. and can be stacked..     its about 6 inches long.. around the bend.. i have used them in pairs.. to come up and then to aim forward to clear the exhaust on cars..

this is just an FYI.. it does not change the speedo ratio...