Originally Posted by JaySHOguy
When you get the correct gear for the transfer case, would you mind posting up the part number? Should be the same number for my '89, right?
Ok...got it in this morning. The part numbers have changed, the 33 tooth sg for mine was 52068155 whereas the Jeep websites always list it as 2538933. Note also that the last 2 digits do NOT reflect the tooth count.
A few words about the parts....there's a number imprinted on the bottom of the gear. On my original gear it was stamped "41"...which matched the tooth count. On the new gear, it's stamped "55" which matches the part number NOT the tooth count. Also note that the new gear is a smaller diameter. See pics below (hope you can make out the numbers).
Install was a piece of cake and I got lucky and put the thing in right the first time. Before I put it in, I ran out and checked the actual speed versus the speedometer. At 50MPH on the speedo, the GPS read 62! After changing the gear, it now reads 48. So I went from reading 12MPH under actual to 2MPH over (no reason for getting a speeding ticket now, eh)!
The speedometer seems to be high by 2MPH at all speeds now (I checked starting at 10MPH and then checked at 10MPH increments). SO.....I think the calculator I used at Jeeptech
is a bit off.
I've seen other charts that list 34 (and 36!) teeth as being correct for 33s with 4.10 gears. I think the 34 toother would probably shave that 2MPH difference off (or at least 1MPH) and make the speedometer more accurate. Don't think the dealer will take the 33 tooth SG back and exchange it for a 34 since it's been installed.
On the bright side, if I should ever go up to 35s, my speedometer will become more accurate.