https://www.thirdgen.org/techbb2/sho...hreadid=338111
I need the parts need to switch out my 2.73 rear to 3.42. See above link.

Please help
ALSO INTERESTED IN A 145 SPEEDO

 

Is this what you need? The red gear and the VSS are from a WC T5 I am assuming it had 3.08 gears. I believe what you need is the purple gear.

 

That's the problem, I'm not really sure what I need.

 

the vss is not the same for the 700r4.

 

Manual speedo gears are definitely different from the auto ones. I did the exact same gear swap (2.73 to 3.42). You need the gray, 15 tooth gear for the output shaft of the trans, and the yellow gear for the end of the cable. I forget how many teeth are on the yellow gear, but there's only one yellow gear available. I think it's 42 or 43. Your stock 2.73 speedo gears are both red in color. I just went down to the chevy dealership and ordered mine. Good luck!

 

i have a 145 speedo. shoot me your email for pics.
thanks!

 

Anybody got a part # for the yellow gear. My car has an electric speedo, it's not a cable driven one.

 

The speedo gears for an Electric Speedo are not the same as the speedo gears for a Cable speedo !!!

I'll see If I can find the chevy gear charts I scanned into my PC awhile ago and will post the images when I have a better answer for Ya' !

 

Here are a few gear charts from the 86 year. ( It's the best I can do ! ) Follow the chart to 3.42 and then look for the MD8 option and the (63) notation...... the (63) indicates a Berlinetta; and the electric speedo gear.


1986 Gear Chart #1


1986 Gear Chart #2


15 tooth GREY PN 8642620
42 tooth Green PN 25513049


I'm sure you will be running 15 or 16 inch tires and the IDEAL driven gear would be a Yellow 41 tooth gear - but I don't have the gear charts or part numbers for the 88-92 years !


P.S. You are going to LOVE that gear swap !!!!!!

 

I'm not positive if the cable style gears will work with the electronic speedo setup, but I know for a fact it works the other way around. I changed to 3.23 gears after running the 3.42's, and the only gray driven gear I had was with an electronic vss unit from a 700r4 out of a 91 GTA. I was able to pop the gear off the shaft of the vss and just put it on the end of the cable style shaft. I had to put a couple of small washers underneath the gear to get the depth right, but it was a piece of cake, and it's worked just fine for a couple of years now. The only thing that was kind of a pain was that I had to change the trans output shaft gear back to the red one. The clip that holds that in place can be a real picnic to release! At a guess, I'd say the cable style gear will probably work with an automatic vss.

 

I think that the main output shaft gear is the same for VSS/speedo cable type, the pain is taking the case apart to swap the gear on the main output shaft, to get the clip off, just press the end of the clip, and at the same time tap the gear untill the tab goes under the gear, then tap the gear off. I have the yellow gear, it came out of a VSS,WC T-5 94, w/3:42 gears, and .62 5th gear, no part # on it, the dealer can get the gear in most cases a day or two, just need the year car, T-5, and color of the gear, the dealer does not track them by # of the teeth, just color, it will just confuse him, with ratios and combos, as all cars use different tire size and gear combos, unless your parts counter guy is in competent, another option is to go to the speedo gear section here and see if another color VSS gear will work with the ratio in your car and color of the mainshaft gear to prevent you from splitting the case.

 

Everyone I've talked to running a 700r4 trans and 3.42 gears use the gray tranny shaft gear and the yellow gear on the end of the cable or vss. Removing the tranny gear isn't too terribly hard. I always put a crescent wrench behind the gear and just tap the wrench with a hammer while holding the tab down. As far as taking the case apart, all you have to do is remove the short tailshaft housing, which only has four bolts holding it. Plus it has on o-ring seal, so you don't even have to replace the gasket either.

 

I was refering to the removal of the T5 mainshaft (output shaft)speedo gear, ---you cannot change that one with the trans in the car---, the 700 you can very easily, I have a lot of good used speedo gears, if you need any let me know the color and type T5/700, and have the gears for the 3:73 T-5 combo figured out, w/245-50-16 tire.

 

Damn, sounds like a real PITA on a T5 then! Anyhow, the original poster has a 700r4 though.

 

I donot have the part # for the 700 gears, I know that I have a set, believe it or not the dealer can get them for cheap, and in a day or so, just tell them this: year car, trans type, specify vss, color of the gears, they usually go by the color, as there is a lot of aplications and gear ratios, @ 25$ for both, and the formula (# of teeth) and color, there is on a link on this site.

 

I need speedo gears for an '88 Camaro with a T-5. New rear end ratio is 3.42 (previously 3.08). I'm told that I need to replace both the drive and driven gear, however they're no longer avaliable from the dealer in Canada. Can anyone help?

Also, I have a 145mph complete cluster for sale. Will trade for a metric 240kmh cluster. PM if interested.

 

I am pretty sure I have a set, let me know the colors of them.

 

Well I finally got everything straight. Went down to the parts dept. They had everthing in stock. The gears I needed, the little clip, the new o ring for the vss, and the tailshaft seal. All in all it cost me less then $16. Now I wish it would get warm enough outside so I can change that rear!!!!