Hello,
I am changing the speed gear to match the tire size and new gears (39) and I can install to the original position of 32-38 flush but when I turn the gear to the 39-45 position a portion of the housing unseats itself therefore not sitting flush. I have messed with this a few times but I cannot get it ti sit flush. Any ideas?

I'm confused by how your describing turning it from one to the other? As I recall the speedo gear is a replaceable part that inserts into the speedo gear housing. The housing is then installed and clocked for proper gear mesh?

I'd imagine if your clocking it too far it would be popping out because it's physically climbing away from the speedo gear/sleeve on the output shaft.

I am also confused by your worked clocked. I am assuming that the word clocked and turn are the same. With the new gear installed the housing fits perfectly in the original position of 32-38 but won’t fit in the 39-45 position. Does the gear housing need to be modified in any way?

Seems like a stupid question but are you sure the new speedo gear is a 39?

39 is stamped on the gear itself. I am going to try and install it in the last position of 32-38 and take it for a spin and see what happens. I may have to modify the housing itself but that will be the last effort.

To me it doesn't make sense that it will fit in the original position and not rotated at 1/3 turn. It's driving me crazy!

Okay, I replaced the housing and the new gear back in the original position (32-38) and checked speed against phone GPS and it off by a half mile per hour... Good enough for me.

Hey, just a learning question...you talk about pos32-38 and 39-45. What does that mean...way back when, when I went from stock wheels to 31's i had to change my speedo gear. 4.0. A/T and a stock 231 TC. So I took what was in there, installed the new gear, calibrated for my change and just put it back together. I don't understand your issue...if you don't mind explaining it..thanks

On the "gear housing" that fits inside of the SYE or transfer case there are a few sets of numbers, such as 32-38 & 39-45, which is the size of the gear (position). I installed a new gear that was 39 therefore I needed to line up the 39-45 #'s in the correct position. See attached image. It wasn't fitting flush in the 39-45 position therefore I switched it back to the second set of numbers and it fit like a glove with no leaks. Thankfully it is only off a half of a mile per hour per GPS.

Ok thanks..that makes much more sense now. Sadly for me i did none of that when i regeared my 92 and my 01. My 01 is a mph or 2 off at 70 based on gps, i thought it was because the gears and tire dia were a little mismatched. Dont even know whats in there now, its been many years.thanks for the learning..If i remember the entire assembly including the big round part with the cutout lockdown slots is one piece, is the numbers you were looking for exactly 180 out so the lockdown slots would still mate with the metal lockdown yoke?