Ring and pinion swap

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Savageftr

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I have an 86 c15 with 3. 08 gears and a th350.

I'm pulling a camper with the truck and it seems a bit too steep for this.

Any issues just buying a 3.73 ring and pinion set? I should just need a new crush washer and set the depth, lash and pinion bearing preload again right?


I'm plan on just keeping it an open diff.
 

Bextreme04

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For the same price as a ring and pinion set and an axle rebuild kit, you could just get a 14bff with open 4.10's or 3.73's... just an option :emotions33:

I have a 2011 Suburban that has 3.08's and we also pull a camp trailer, its a dog. I bought a set of 4.10's for both front and rear with the axle rebuild kits for both as well. I went with 4.10's since we have a 6L80E that has a double overdrive and we pull a lot through mountains here in the Pacific North-west.
 

Savageftr

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For the same price as a ring and pinion set and an axle rebuild kit, you could just get a 14bff with open 4.10's or 3.73's... just an option :emotions33:

I have a 2011 Suburban that has 3.08's and we also pull a camp trailer, its a dog. I bought a set of 4.10's for both front and rear with the axle rebuild kits for both as well. I went with 4.10's since we have a 6L80E that has a double overdrive and we pull a lot through mountains here in the Pacific North-west.


My buddy actually has a 14 bolt full floater I can have for next to nothing but I want to keep my stock rally wheels. I thought a ring and pinion swap would be the cheapest. about $250 plus/minus.

The semi floating 14 bolts are hard to find I've heard and not cheap either.
 

C10MixMaster

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I have an 86 c15 with 3. 08 gears and a th350.

I'm pulling a camper with the truck and it seems a bit too steep for this.

Any issues just buying a 3.73 ring and pinion set? I should just need a new crush washer and set the depth, lash and pinion bearing preload again right?


I'm plan on just keeping it an open diff.

get an install kit there not that expensive ~ $70. you will need the shims / seal / crush sleeve / lock nut at the minimum. and if your going that far do the bearings and ring bolts to , which are all in the install kit.

GM 12-Bolt rear diff UPGRADE: Positraction and gear swap | Hagerty DIY - YouTube this will give you an idea of what needs to be done.
 

Snoots

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I like the gear swap (3.73) but I'd spring for a posi carrier.
 

Grit dog

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For the same price as a ring and pinion set and an axle rebuild kit, you could just get a 14bff with open 4.10's or 3.73's... just an option :emotions33:
Why would one go through that brain damage of making a 8 lug axle work under a 5 lug truck and not look like a pos with mis matched wheels?
Can't tell by the :emotions33: if you are serious or joking.
 

Grit dog

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I have an 86 c15 with 3. 08 gears and a th350.

I'm pulling a camper with the truck and it seems a bit too steep for this.

Any issues just buying a 3.73 ring and pinion set?

Depends how fast you want to drive on the highway.
If your truck actually has a Turbo 350 swapped in it, it will be screaming at highway speeds with deep gear and the little tires that are on it.
Think about what you want out of the truck. If just for towing, 3.73s or even 4.10s will be great, but not if you drive it 70mph+ on the highway. That's 3000-3300 rpms (3.73 vs 4.10) at 70 mph in drive.
 

Bextreme04

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Why would one go through that brain damage of making a 8 lug axle work under a 5 lug truck and not look like a pos with mis matched wheels?
Can't tell by the :emotions33: if you are serious or joking.

Mostly joking... but it is still a valid option. For a 2wd, it's pretty easy to convert to the bigger 3/4 ton 8-lug front rotor and caliper also... but if he has nice wheels and tires that's obviously not a good one.
 

Savageftr

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Depends how fast you want to drive on the highway.
If your truck actually has a Turbo 350 swapped in it, it will be screaming at highway speeds with deep gear and the little tires that are on it.
Think about what you want out of the truck. If just for towing, 3.73s or even 4.10s will be great, but not if you drive it 70mph+ on the highway. That's 3000-3300 rpms (3.73 vs 4.10) at 70 mph in drive.

The TH350 is factory not swapped. Its the MX1 rop code for a TH350C with the converter lockup. I'm happy driving 55 or 60 on the highway.

The only longer trips I will be taking will be pulling the camper. I want to be able to drive 55 ish on windy days and not smoke the trans. Right now when its really windy you can tell the trans is under some serious load, hoping lower gearing should help take some stress off the engine/trans.
 

Savageftr

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I like the gear swap (3.73) but I'd spring for a posi carrier.

It would be nice but I'm not racing it or driving in the mud so the only use for it would be the occasional burn out...

I figure less traction = less breaking ****

I have lots of other **** I could spend $700 on right now that I actually need
 

Savageftr

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I like the gear swap (3.73) but I'd spring for a posi carrier.

It would be nice but I'm not racing it or driving in the mud so the only use for it would be the occasional burn out...

I figure less traction = less breaking ****

I have lots of other **** I could spend $700 on right now that I actually need
 

WesN

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Be aware that there is two different ring and pinions (thick vs thin) that will depend on which carrier you have. Carriers are made for a certain range of gear ratios and it will determine which gears will work with you stock carrier.
 

Ken Boellner

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Just changed the 3:08's in my to 3:73. You have to change the carrier also.
 

MikeB

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Carrier "break" for 8.5" 10-bolt is 2.56/2.73. That means 3.73 gears would work with your carrier even if your truck had 2.73 gears. Simply google it.

Also, I would opt for a crush sleeve eliminator kit (spacer+shims). That way you don't need to torque the pinion nut to 300 lb/ft or more to crush a sleeve, and then throw it away if you mess up. https://www.yukongear.com/productdetails.aspx?ProdID=8280
 

SquareRoot

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Someone's about to go down a rabbit hole. On the plus side, if your truck has the factory 305 you ain't gotta worry bout breaking anything.
 

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