im about to swap a rear end from a 99 z28 into my 91 z28, since the gears are different is my speedo going to be off after the swap?

 

Yes your speedo will be off.

Jay

 

ok. anyone know what i have to do to get it right again?

 

sorrym just did a search and founs some answers. anyone know what gears were in a 99 z28 and what size speedo gears i will need to replace mine with?

 

Here's how to determinne what ratio the rear is (jerk the diff cover and look): numbers are stamped on the ring and pinion:

41 : 15 = 2.73
40 : 13 = 3.08
42 : 13 = 3.23
41 : 12 = 3.42
41 : 11 = 3.73

You may have to swap the drive/driven gears in the transmission--those will depend on the what tranny you're running, auto or manuel. A search should provide more info.

JamesC

 

A 99 Z28 could come with 2.73 gears (auto), 3.23 gears (auto), or 3.42 gears (stick). A search of this forum will tell you what speedo gears you need in your transmission.

 

thanx guys

 

is there an easier way than changing the speedo gears in the trans everytime i switch gear sizes or tire sizes? can i get an electrical vss to hook up to my speedo or somthing that will let me program in gear and tire size and respond accordingly?