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kennythewelder

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Or, you can pull the cover, and count the teeth then divide. Dont remember the formula though.
 

kennythewelder

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There are a ton of videos on doing diff work on youtube.
 

Ryline

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Welcome to the forum. Good intro, good story. Just rebuilt my diff on my 97. What are you doing to yours.
Thanks Kenny, appreciate that. Well I’m driving this truck back up to Michigan where i know a group of guys who build high performance drag cars. I’ve painted many of their race & show cars as well. Since I’m not the most knowledgeable with performance, and they know the trucks history. They are going to redo or install new heads, cam, lifters and so on. As well as install a set of headers I’ve had forever. With them doing that I wanted to make sure my axle after all these years was still in good shape. But I’ve never taken the diff cover off and not sure on which fluid to add. People keep telling me about additives which made it more confusing. Almost have the brakes together and if the wheel doesn’t catch. Then my mystery problem of this weird but slight pull only on a 90 degree turn leads me to think I have an internal issue with the gears.
 

Ryline

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Or, you can pull the cover, and count the teeth then divide. Dont remember the formula though.
See I don’t know anything about counting and dividing. I’m thinking I should replace the fluid and drop that rear cover. Just to be safe before the 1300 mile drive.
 

Ryline

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Here is a link to a video on how to get the gear ratio. Oi know its a s-10 but that doesnt matter.
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Wow, I just watched the first minute and he seems thorough. If I was to drop my diff cover, besides visually broken pieces. Is there anything else you recommend when checking to see how good of shape the gears are in?
 

kennythewelder

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Get your buds to pull the cover while your there. Its very easy to do. You only need additives if the rear end is limited slip with clutches in the carrier. I installed an Eaton trutrac in mine with 373 gears. I have 275/60-15 tires, so that gear ratio is about perfect for me. Look at the inside of the glove box door at the RPO codes. G80 is a limited slip. The RPO codes will tell you what options the truck came with when it was new. Just google RPO code reader.
 

Ryline

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Get your buds to pull the cover while your there. Its very easy to do. You only need additives if the rear end is limited slip with clutches in the carrier. I installed an Eaton trutrac in mine with 373 gears. I have 275/60-15 tires, so that gear ratio is about perfect for me. Look at the inside of the glove box door at the RPO codes. G80 is a limited slip. The RPO codes will tell you what options the truck came with when it was new. Just google RPO code reader.
Ok perfect, thank you I’ll check that out. Much appreciated!!
 

kennythewelder

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So if the diff isnt making noise when driving, your most likely ok. If the diff is the normal open carrier that is in most of these trucks, then it just takes normal 80-90 gear oil. Just did mine with valvoline dyno oil. I dont need additives.
 

Ryline

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So if the diff isnt making noise when driving, your most likely ok. If the diff is the normal open carrier that is in most of these trucks, then it just takes normal 80-90 gear oil. Just did mine with valvoline dyno oil. I dont need additives.
Nope no noises, and I’ve never changed the fluid. It’s the original.
 

kennythewelder

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Here is mine as I rebuilt it about 3 months ago. The second and 3ed pic is the open carrier. The last pic is the trutrac installed
 

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