Gears change nightmare

josehf34

Active Member
Joined
Dec 18, 2013
Messages
257
Reaction score
8
I'm doing a gears change on my '74 fury but is starting to be a real nightmare!

According to the differential cover bolt pattern my axle is an 8.25 but I'm starting to think that maybe isn't due to so much problems

IMG_4352 (1).JPG


The stock gears were 2.73 (i think...) and the new gears are 3.55, the new pinion and gear are a kit sold by Richmond Gear Excel and the installation kit is a Motive Gear super kit.

The pinion and gear are successfully installed but now I've a problem with my carrier bearings, apparently the new bearings doesn't fit in my axle housing (see second image attached), I checked the list parts of the installation kit and everything is correct, the bearings part numbers are correct so I don't know why them doesn't fit

The second problem is that one of the adjusters in my axle is broken (see third attached image), I mean, when I disassembled the unit it fell broken in my hand. Is it easy to find? can I buy one or will be needed to buy a pair?

IMG_4349.JPG


IMG_4354.JPG
 
Did you ck the new bearing part no's against the old bearings? The races also.
 
Did you ck the new bearing part no's against the old bearings? The races also.

Yes they are different, the old part number is LM102949 and LM102910 and new part number is LM603012 (just as the instalation kit parts list says)
 
So the pinion and pinion bearings are installed and you are trying to get the carrier bearings on and the carrier installed, right. If the bearing no's don't match something is wrong. Wrong for the application.
 
I just ck'd rock auto the LM102910 is the correct race for the 8 1/4. I don't know what the LM603012 fits but I say it's wrong
 
I just ck'd rock auto the LM102910 is the correct race for the 8 1/4. I don't know what the LM603012 fits but I say it's wrong

I'm going to look for that race tomorrow, maybe the installation kit is wrong but I think is a bit weird because most of the installation kits I've found on internet says that the LM603012 in the carrier bearing
 
Fellas.. I wanted to ask ya.. I'm Doing PM on my New Yorker before Carlisle , I want to change the axle fluid just because.. The axle sounds fine when driving, no whining noise of any kind, my question is what type of axle/gear oil should I use? Should I remove the diff cover or is there a drain plug on the axle? No I haven't looked yet. Lol, Or should I just referred to my service manual can answer all my questions. Thanks in advance for your thoughts.
 
For an 8 3/4" there's no removable cover but there's a big square head pipe plug that you can remove to check fluid level. It should be no less than 1/2" below the fill hole and you can fit your finger in as a dip stick. If it's not making any noise and the fluid level is fine I'd leave it be. If you actually want to change the fluid in these you'll have to siphon it out through the fill hole unless you want to pull the shafts and remove it completely, new gasket, etc..
 
Going by his "handle" and avatar pic, he has a 75 NYB-which means he'll very likely have a 9.25 diff behind the 440/727 standard drivetrain. The 9.25 Diff cover has a fill hole...On my past Imperials, it was a threaded plug that over the years rusted and deformed...I replaced it with a rubber plug used on later trucks like you see here (highly recommended).

I don't know what year they transitioned to the rubber plug.

axle_chrysler_925_3.jpg
 
For an 8 3/4" there's no removable cover but there's a big square head pipe plug that you can remove to check fluid level. It should be no less than 1/2" below the fill hole and you can fit your finger in as a dip stick. If it's not making any noise and the fluid level is fine I'd leave it be. If you actually want to change the fluid in these you'll have to siphon it out through the fill hole unless you want to pull the shafts and remove it completely, new gasket, etc..

Perfect.. That's what I needed. I'll get under the car this week to see what's what. Thank you.

Thanks Mr. C as well. Just want her to as fresh as she can be for the road.
 
The 8.25 & 9.25 have cover on the rear I would open it up and clean it out, there is often a lot of sludge at the bottom.
 
Fellas.. I wanted to ask ya.. I'm Doing PM on my New Yorker before Carlisle , I want to change the axle fluid just because.. The axle sounds fine when driving, no whining noise of any kind, my question is what type of axle/gear oil should I use? Should I remove the diff cover or is there a drain plug on the axle? No I haven't looked yet. Lol, Or should I just referred to my service manual can answer all my questions. Thanks in advance for your thoughts.
I would use 75w90 gear oil, you can upgrade to synthetic for added protection
 
Back
Top