[MRGTO2U]

Hi everyone. I just installed a new Auburn Posi and 3.55 gear in my 68 GTO. Wow! what a difference going from a 2.78 open to the 3.55. Great acceleration! As you all know my speedometer is way off. Doing 45 MPH she marks almost at 60. What do I have to change, the speedometer gear? Is this the part I need:

3.55 1362049 42 GREEN X 1362293 PX 16

I found this from a chart at: http://www.teufert.net/speedo/68-gto-400.htm

This has both the Gear and the Sleeve and Seal Assy. My Tranny is a TH400.

I really appreciatte comments and advice. Thanks to all!!
JG

Do I need both the gear and the Sleeve and Seal????

[screamingchief]

I always check this resource for my speedo gear needs:

http://www.tciauto.com/tech_info/speedo_gears.htm

You should replace the o-rings/seals when changing gear(s) for the sake of being thourough,but the sleave should'nt be needed necessarrily.