Shade tree gear change

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roundhouse

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You’re a 2wd ?
1/2 ton ?

What trans did you swap in ?
 

roundhouse

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Yep, 2wd half ton, I put a 700r4 in
Your 700 have a TV cable ?
You got it adjusted properly I hope

Any back axle from a squarebody should fit

Someone else can chime in but I think axles from blazers and 1/2 ton burbs are the same as the pickups

Not as easy to find as you might think because the 10 and 12 bolt rear axles are really weak and break easily
But they aren’t worth much
I took a 3.73 rear axle to the crusher with the shell of my parts truck

You might need a different U joint and it’s possible the driveshaft might need to be shortened
You won’t know until you get the replacement axle and install it

But getting a shaft made shorter is a lot easier and cheaper than making it longer

Do some reading on coloradoK5.com
 

crazy4offroad

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R&P swap isn't impossible, especially since it's 2WD, only 1 set to do. You'll need a caliper micrometer, dial indicator, hydraulic press or access to one and a bearing cup, and a good, high-torque air impact in the neighborhood of 450 ft/lbs or better. You'll need a thick gear set to run 3.73s on a 3-series carrier. Avoid the shim plate R&P sets. You'll also need a bearing and install kit.

When you pull the carrier, if the shims are between the carrier bearings and the axle housing you need to catch them and note their thickness and orientation. It will come in handy to try to put the same amount of shim back when you re-assemble and get you in the ballpark. Some 10 and 12 bolts have the shims under the bearing between the bearing and carrier. In that case you'll have to pull the bearings and mic the shims. You'll want to pull the bearings and replace them either way. No sense in running 40 year old bearings on a new gear set.

The pinion bearing races can be removed from the housing with a drift and hammer. You'll need to press the bearings off the old pinion so you can mic those too. Some people dont. They'll throw 0.010" in there and see what they got which is fine. It is likely it will have to be pressed off again and more shim added or some removed either method you try. The pinion bearings have to have a measure of preload on them when the pinion nut is tightened. For setup you don't have to be exact but you don't want it to be loose. Usual preload is about 24 inch-pounds so it's barely discernible as drag but it's too low to get right with a ft/lb torque wrench. If you can spin the pinion easy enough that when you let go it stops it's just about right. It will run in a little anyway. Most of your ring gear bolts are going to be left hand thread so don't be surprised if you have to set your impact to "righty loosey". Also they're assembled with thread locker so they will be tough to get off.

Once it comes time to place the carrier, you'll want to put your shims in after the fact between the race and the axle housing. You may need a pry bar to get them in, it should be a pretty tight fit. A ratchet strap wrapped around the axle housing will help hold the carrier in while you put your shims in and bearing caps on. You'll torque your caps on and then run a mesh pattern to see how it looks. Don't worry about backlash right away unless it sounds like it has way too much. Moving carrier shims around will tighten that up. There are a lot of google images with what to look for as far as mesh pattern is concerned. You move shims from one side to the other till you tighten up the pattern but not too deep into the root of the gear. If it's too deep the pinion needs shim removed. Too shallow and the pinion needs a little more shim. All this also affects the pattern in relation to the heel and toe of the ring gear.

Once you get a good looking drive and coast pattern check your backlash. You're looking for typically 0.005" - 0.008" for a new gear set. A lot of times just moving shims left or right of the carrier can adjust your backlash into spec but it may mess with your mesh pattern which may make you have to adjust your pinion depth. If you're not the kind of person willing to handle a 30 pound chunk of iron and steel a dozen times to get it right, don't bother even starting. If you are and you've got it this far along, there's a crush collar that goes between the pinion bearings to set preload. If you overtighten the crush sleeve you can stretch it back out with a hammer and the horn on an anvil or back of a vise. Some people opt for the crush sleeve eliminator kit which is just a stack of washers and some shims which takes a lot of trial and error to get the preload right.

Once you're finally ready to tighten the pinion nut, use plenty of red thread locker, and use a chisel and hammer to to "ding" the nut to make it hold stronger. It takes a lot of impact to run down the pinion nut. You can put a pipe wrench on the pinion yoke and let it turn over against the ground while you're tightening. You do not want to use the impact on the pinion nut with the carrier and ring gear in place. It can damage the gear teeth.

So there ya go. You may want to just look around for a 3.73 or even 4.10 rear end to see what's out there. Use a gear ratio calculator and fine tune your final drive RPMs with tire size.
 

ajd89

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R&P swap isn't impossible, especially since it's 2WD, only 1 set to do. You'll need a caliper micrometer, dial indicator, hydraulic press or access to one and a bearing cup, and a good, high-torque air impact in the neighborhood of 450 ft/lbs or better. You'll need a thick gear set to run 3.73s on a 3-series carrier. Avoid the shim plate R&P sets. You'll also need a bearing and install kit.

When you pull the carrier, if the shims are between the carrier bearings and the axle housing you need to catch them and note their thickness and orientation. It will come in handy to try to put the same amount of shim back when you re-assemble and get you in the ballpark. Some 10 and 12 bolts have the shims under the bearing between the bearing and carrier. In that case you'll have to pull the bearings and mic the shims. You'll want to pull the bearings and replace them either way. No sense in running 40 year old bearings on a new gear set.

The pinion bearing races can be removed from the housing with a drift and hammer. You'll need to press the bearings off the old pinion so you can mic those too. Some people dont. They'll throw 0.010" in there and see what they got which is fine. It is likely it will have to be pressed off again and more shim added or some removed either method you try. The pinion bearings have to have a measure of preload on them when the pinion nut is tightened. For setup you don't have to be exact but you don't want it to be loose. Usual preload is about 24 inch-pounds so it's barely discernible as drag but it's too low to get right with a ft/lb torque wrench. If you can spin the pinion easy enough that when you let go it stops it's just about right. It will run in a little anyway. Most of your ring gear bolts are going to be left hand thread so don't be surprised if you have to set your impact to "righty loosey". Also they're assembled with thread locker so they will be tough to get off.

Once it comes time to place the carrier, you'll want to put your shims in after the fact between the race and the axle housing. You may need a pry bar to get them in, it should be a pretty tight fit. A ratchet strap wrapped around the axle housing will help hold the carrier in while you put your shims in and bearing caps on. You'll torque your caps on and then run a mesh pattern to see how it looks. Don't worry about backlash right away unless it sounds like it has way too much. Moving carrier shims around will tighten that up. There are a lot of google images with what to look for as far as mesh pattern is concerned. You move shims from one side to the other till you tighten up the pattern but not too deep into the root of the gear. If it's too deep the pinion needs shim removed. Too shallow and the pinion needs a little more shim. All this also affects the pattern in relation to the heel and toe of the ring gear.

Once you get a good looking drive and coast pattern check your backlash. You're looking for typically 0.005" - 0.008" for a new gear set. A lot of times just moving shims left or right of the carrier can adjust your backlash into spec but it may mess with your mesh pattern which may make you have to adjust your pinion depth. If you're not the kind of person willing to handle a 30 pound chunk of iron and steel a dozen times to get it right, don't bother even starting. If you are and you've got it this far along, there's a crush collar that goes between the pinion bearings to set preload. If you overtighten the crush sleeve you can stretch it back out with a hammer and the horn on an anvil or back of a vise. Some people opt for the crush sleeve eliminator kit which is just a stack of washers and some shims which takes a lot of trial and error to get the preload right.

Once you're finally ready to tighten the pinion nut, use plenty of red thread locker, and use a chisel and hammer to to "ding" the nut to make it hold stronger. It takes a lot of impact to run down the pinion nut. You can put a pipe wrench on the pinion yoke and let it turn over against the ground while you're tightening. You do not want to use the impact on the pinion nut with the carrier and ring gear in place. It can damage the gear teeth.

So there ya go. You may want to just look around for a 3.73 or even 4.10 rear end to see what's out there. Use a gear ratio calculator and fine tune your final drive RPMs with tire size.
That seems like some really good info! Ive never swapped gears before but it sounds like you might have a time or two! Lol!
 

Obwonkonobe

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R&P swap isn't impossible, especially since it's 2WD, only 1 set to do. You'll need a caliper micrometer, dial indicator, hydraulic press or access to one and a bearing cup, and a good, high-torque air impact in the neighborhood of 450 ft/lbs or better. You'll need a thick gear set to run 3.73s on a 3-series carrier. Avoid the shim plate R&P sets. You'll also need a bearing and install kit.

When you pull the carrier, if the shims are between the carrier bearings and the axle housing you need to catch them and note their thickness and orientation. It will come in handy to try to put the same amount of shim back when you re-assemble and get you in the ballpark. Some 10 and 12 bolts have the shims under the bearing between the bearing and carrier. In that case you'll have to pull the bearings and mic the shims. You'll want to pull the bearings and replace them either way. No sense in running 40 year old bearings on a new gear set.

The pinion bearing races can be removed from the housing with a drift and hammer. You'll need to press the bearings off the old pinion so you can mic those too. Some people dont. They'll throw 0.010" in there and see what they got which is fine. It is likely it will have to be pressed off again and more shim added or some removed either method you try. The pinion bearings have to have a measure of preload on them when the pinion nut is tightened. For setup you don't have to be exact but you don't want it to be loose. Usual preload is about 24 inch-pounds so it's barely discernible as drag but it's too low to get right with a ft/lb torque wrench. If you can spin the pinion easy enough that when you let go it stops it's just about right. It will run in a little anyway. Most of your ring gear bolts are going to be left hand thread so don't be surprised if you have to set your impact to "righty loosey". Also they're assembled with thread locker so they will be tough to get off.

Once it comes time to place the carrier, you'll want to put your shims in after the fact between the race and the axle housing. You may need a pry bar to get them in, it should be a pretty tight fit. A ratchet strap wrapped around the axle housing will help hold the carrier in while you put your shims in and bearing caps on. You'll torque your caps on and then run a mesh pattern to see how it looks. Don't worry about backlash right away unless it sounds like it has way too much. Moving carrier shims around will tighten that up. There are a lot of google images with what to look for as far as mesh pattern is concerned. You move shims from one side to the other till you tighten up the pattern but not too deep into the root of the gear. If it's too deep the pinion needs shim removed. Too shallow and the pinion needs a little more shim. All this also affects the pattern in relation to the heel and toe of the ring gear.

Once you get a good looking drive and coast pattern check your backlash. You're looking for typically 0.005" - 0.008" for a new gear set. A lot of times just moving shims left or right of the carrier can adjust your backlash into spec but it may mess with your mesh pattern which may make you have to adjust your pinion depth. If you're not the kind of person willing to handle a 30 pound chunk of iron and steel a dozen times to get it right, don't bother even starting. If you are and you've got it this far along, there's a crush collar that goes between the pinion bearings to set preload. If you overtighten the crush sleeve you can stretch it back out with a hammer and the horn on an anvil or back of a vise. Some people opt for the crush sleeve eliminator kit which is just a stack of washers and some shims which takes a lot of trial and error to get the preload right.

Once you're finally ready to tighten the pinion nut, use plenty of red thread locker, and use a chisel and hammer to to "ding" the nut to make it hold stronger. It takes a lot of impact to run down the pinion nut. You can put a pipe wrench on the pinion yoke and let it turn over against the ground while you're tightening. You do not want to use the impact on the pinion nut with the carrier and ring gear in place. It can damage the gear teeth.

So there ya go. You may want to just look around for a 3.73 or even 4.10 rear end to see what's out there. Use a gear ratio calculator and fine tune your final drive RPMs with tire size.
WAYYYY more info than I ever could’ve hoped for, but I think I actually understand most of that, thank you!! I should have all of those tools actually, so I’ll start saving for the gear set now and try to do it over the break. Any suggestions on brands for gears, bearings etc? Does anyone make a kit?
 

crazy4offroad

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Richmond or USA Gear. I would stay away from Motive Gear. Make sure you have an assortment of steel slugs and chunks of heavy bar stock for the press, and make sure the press's operating range is large enough to place the whole carrier in. Removing the bearings can be a real bitch. I did a write up about it here a while back
https://www.gmsquarebody.com/threads/ring-pinion-how-to.250/
but thanks to imageshack most of the images are lost. I've thought about staging some parts and procedures for pictures and replacing the broken ones, may do that this winter. Even though the write up is about the 14 bolt, most of the information is relative with the exception of the removable pinion housing and the carrier spanner adjusters of the 14 bolt.
 

Obwonkonobe

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Richmond or USA Gear. I would stay away from Motive Gear. Make sure you have an assortment of steel slugs and chunks of heavy bar stock for the press, and make sure the press's operating range is large enough to place the whole carrier in. Removing the bearings can be a real bitch. I did a write up about it here a while back
https://www.gmsquarebody.com/threads/ring-pinion-how-to.250/
but thanks to imageshack most of the images are lost. I've thought about staging some parts and procedures for pictures and replacing the broken ones, may do that this winter. Even though the write up is about the 14 bolt, most of the information is relative with the exception of the removable pinion housing and the carrier spanner adjusters of the 14 bolt.
Richmond or USA gear got it, thanks again! And if you’ve ever got some spare time that’d be great to update that guide.
This is the press I have, but mines a bit older and a little bigger I think

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crazy4offroad

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I don't know if you'll get the bearings off with an arbor press, you might be able to, they're rated at about 2 tons. I have this 10-ton hydraulic from Northern. You may end up having to take the carrier and pinion to a shop and have them do the press work and hope you get the shims right the first time.

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Camar068

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found a shop that does swaps, engine rebuilds, not your average shop is what I'm getting at. He quoted me $175 per axle to change the ratio. That did not include swapping out all the bearings, just the gears. Just an FYI.
 

Obwonkonobe

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found a shop that does swaps, engine rebuilds, not your average shop is what I'm getting at. He quoted me $175 per axle to change the ratio. That did not include swapping out all the bearings, just the gears. Just an FYI.
WOW that’s the cheapest I’ve ever heard of? What shop is it?
 

Obwonkonobe

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I don't know if you'll get the bearings off with an arbor press, you might be able to, they're rated at about 2 tons. I have this 10-ton hydraulic from Northern. You may end up having to take the carrier and pinion to a shop and have them do the press work and hope you get the shims right the first time.

You must be registered for see images attach
I’d bet my press isn’t up to it then, I’ll keep an ear out for one
 

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I have a 1992 10 bolt I changed from a 308 pegleg to a 410 limited slip. Eaton carrier and richman gears. Used factory shims from original setup. Worked flawless. Used die grinder to remove pinion bearing to get shim out, so no press was needed. Ran for several years untill I changed my setup to a big block and th400.
 

roundhouse

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found a shop that does swaps, engine rebuilds, not your average shop is what I'm getting at. He quoted me $175 per axle to change the ratio. That did not include swapping out all the bearings, just the gears. Just an FYI.
Usually about $650+ per axle

Sometimes more if you need seals and bearings
 

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