Differential gear conundrum

Craig 85

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I use Permatex Right Stuff gasket maker and a gasket. They have small bottles available.

Also when the cover is off, look at the numbers stamped on the ring gear. It will tell you the ratio you actually have. In the photos below, the 7 digit numbers starting with 3 is the part number. 10 - 41 & 11 - 41 are gear ratios. The last 3 numbers are date codes. These sample are for a Chevelle.

Divide the the numbers into 41.
10-41 = 4.10
11-41 = 3.73

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Bextreme04

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Never use gasket maker AND a gasket. I have seen and had good luck with "The Right Stuff" as well. I personally use only a gasket on my 14BFF rear and 10 bolt front with no issues or leaks either. Combining a gasket maker and gasket together is a recipe for leakage that I have seen many, many times..... don't do it.
 

My78truck

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Never use gasket maker AND a gasket. I have seen and had good luck with "The Right Stuff" as well. I personally use only a gasket on my 14BFF rear and 10 bolt front with no issues or leaks either. Combining a gasket maker and gasket together is a recipe for leakage that I have seen many, many times..... don't do it.

Okay, have all the pieces to the maintenance (Fel-Pro gasket, gear oil & 2 cans of Brakleen) now just need the weather to cool down a little. I know I should not use any "gasket maker" but should I use some gasket adhesive when setting the gasket? If so, what brand do you recommend.
 

AKguy

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Lots of choices. This is what I use.

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My78truck

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Okay ........ ALL DONE!!!! gear oil pretty dark, cleaned gears inside housing using 2 cans of Brakleen, cleaned face of housing and cover, used gasket shellac to attach gasket to both faces (everyone wanted to sell me gasket maker..........uh NO!!!! ), bolts clean and replaced and torque to 20# (per service manual). About 1.75 liters of new gear oil, plugged and done!!! Also took pics of the numbers on the small gear rings for future reference - which I assume are part numbers. Also figured out I do NOT have limited slip. Easy-peasy!!! :cocktail:
 
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78C10BigTen

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Okay ........ ALL DONE!!!! gear oil pretty dark, cleaned gears inside housing using 2 cans of Brakleen, cleaned face of housing and cover, used gasket shellac to attach gasket to both faces (everyone wanted to sell me gasket maker..........uh NO!!!! ), bolts clean and replaced and torque to 20# (per service manual). About 1.75 liters of new gear oil, plugged and done!!! Also took pics of the numbers on the gear rings for future reference - which I assume are part numbers. Also figured out I do NOT have limited slip. Easy-peasy!!! :cocktail:
What did your ratio turn out to be?
 

Paladin

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Awesome!! Good job!!! Got to say it's nice to hear of a gal who ain't scared to get oily and greasy doing her own mechanic work!! Hmmm.... warm fuzzies...... LOL:happy160: A toast to you Becky!!!!!!!!
 

My78truck

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What did your ratio turn out to be?

Unfortunately, the numbers on the ring gear were not showing. The only numbers I have are proabably part #'s. I failed at that - sorry :( I know that it is a 3.40 axle.

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My78truck

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Awesome!! Good job!!! Got to say it's nice to hear of a gal who ain't scared to get oily and greasy doing her own mechanic work!! Hmmm.... warm fuzzies...... LOL:happy160: A toast to you Becky!!!!!!!!

Thanks!!! I am the daughter of a mechanic - grease doesn't scare me, that is what they make Goop for right???? (I like the orange :) ) and nail brushes, soft scrub and even acetone at times. I don't wear gloves........probably should with all the chemicals I have had my hands in.
 

My78truck

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I want to take this time to thank everyone that helps me with my issues - which I have posted many on this board. I really appreciate and rely on your expertise and you do not just shrug me off because I am a woman, or make me feel my questions are stupid (even if they may be ;) ) I am the daughter of a 50+ year career mechanic whom I am the lucky recipient of ALL his MAC tools in 2 tool HUGE toolboxes. I can still pick his brain every now and then, but at 80+ years old, it is getting foggy and doing the work just isn't happening. I like learning, I don't mind getting my hands dirty, and as long as I have people holding my hand and giving me encouragement, I will try.

So THANKS TO ALL OF YOU!!!! Cheers :cheers:
 

MikeB

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One more question, do you suggest I get a real gasket or use the RTF gasket maker when I reassemble.
I recently used this stuff instead of a gasket. Be sure the follow the instructions. After applying to one side, you let it set for an hour with the cover bolts just hand-tightened. Then you torque to spec and wait a day before adding diff lube. Not great for someone in a hurry, so shops probably won't use it. Oh yeah, make sure both surfaces are clean. Wipe them down with something like lacquer thinner.

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My78truck

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I recently used this stuff instead of a gasket. Be sure the follow the instructions. After applying to one side, you let it set for an hour with the cover bolts just hand-tightened. Then you torque to spec and wait a day before adding diff lube. Not great for someone in a hurry, so shops probably won't use it. Oh yeah, make sure both surfaces are clean. Wipe them down with something like lacquer thinner.

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Reassembled and used gasket shellac. So far, so good. No leaks
 

Raider L

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@Bextreme04,

I looked most of all the listings on @RetroC10Sport 's post and it's incredible. But so many were so similar over a whole span of years.
 

Raider L

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I used to use the aviation Permatex on my '48 Harley Pan Head. My Harley never leaked like all these other guys bikes did. Except where it's supposed to leak and that's inside the timing chain cover. The drive chain gets it's oil from a small orifice and it leaks inside the cover to lube the chain. It in turn has a small leak from the back of the cover and is supposed to be there.

I just did a clean up of my rear end a few months ago and boy did it stink! Mine hadn't been changed in twenty-five years. To my surprise it was spotless! The lube was just a bit dark and there wasn't any goop or crud inside the case whatsoever and the ring gear was pristine. I didn't expect to see how clean it was in there. I used a Richmond Gears overhaul kit. Everything but the axles got changed back when I rebuilt the truck.
 

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