Hello, I have a 95 caprice that came with the 4.3 and a 7.5 rear end. I now have the 5.7 engine and I want to upgrade my rear end to the 8.5. Which cars or trucks besides the impala ss can i get the rear end from?
Quayenglish
That's to remind you that you need the driveshaft too, your L99 driveshaft is a smidge too long.
For starters:
ANY '91-'96 Caprice or Roadmaster wagon (technically this axle assembly is slightly better than a sedan's; it works)
ANY '91-'96 Roadmaster sedan
ANY '91-'96 Caprice sedan with a 5.7L L05 or LT1 V8
ANY '91-'96 Fleetwood axle will work, but the driveshaft will be too long
Someone will refine this answer, but many GM '1500' pickups or SUVs with 5.0L or 5.7L V8s should have an 8.5" axle.
I wouldn't put a wagon diff under a sedan. It won't fit correctly. Look for a sedan rear with disc brakes.
Rearend Widths
I'm not sure if this belongs here, in wheels and tires, exterior, or suspension. Can we get a list of what the rear ends are and what widths are? I know it used to be on here but I searched some and I think it's gone. I'd like to know the widths for the drum, Civie Disc (did those exist?)...
www.impalassforum.com
In regards to this car in particular and a wagon diff.
You say you have 26 inch wheels, can your wheel - tire combination stand moving out towards the fender wells 1.5 inches ?
If you ever have plans of rear discs on this car, the wagon axle stand off dimension makes it more costly because there is custom work involved.
If you do go ahead with a wagon diff, in my humble opinion, when choosing extended arms, which you say are necessary to you, select ones with joints, like the roto joint.
This because they will account for the different angles the arms will sit at due to the wagon axle mounting points.
The wagon sping pads being wider PLUS you moving the axle back , is going to get weird.
Plan on making new axle pads.
You dont have to completely remove the old, just grind the locating ring flat, park the new locators on top and weld them in place.
Even a stock spring ,in a stock wagon ,with a stock diff , in the stock postion, does not sit well.
I move mine a little when doing housings.
Two of my 3
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You say you have 26 inch wheels, can your wheel - tire combination stand moving out towards the fender wells 1.5 inches ?
If you ever have plans of rear discs on this car, the wagon axle stand off dimension makes it more costly because there is custom work involved.
If you do go ahead with a wagon diff, in my humble opinion, when choosing extended arms, which you say are necessary to you, select ones with joints, like the roto joint.
This because they will account for the different angles the arms will sit at due to the wagon axle mounting points.
The wagon sping pads being wider PLUS you moving the axle back , is going to get weird.
Plan on making new axle pads.
You dont have to completely remove the old, just grind the locating ring flat, park the new locators on top and weld them in place.
Even a stock spring ,in a stock wagon ,with a stock diff , in the stock postion, does not sit well.
I move mine a little when doing housings.
Two of my 3
Well, I was talking about how he needed to look for a sedan rear because the wagon rear won't fit correctly, Marky shared a post that tells them exactly why there will be an issue and finally 95Wagon told them that some modifications would be needed in order for the wagon rear to fit and it would still be much wider.
People have put sedan rears in wagons even though they don't bolt up properly and the reverse could be done as well, it just won't bolt up properly. Personally I would never do either but that's just me.
People have put sedan rears in wagons even though they don't bolt up properly and the reverse could be done as well, it just won't bolt up properly. Personally I would never do either but that's just me.
Go with what Sinister said. Pick a rear from a RMS, or a Caprice sedan with the LO5 or LT1. The drive shaft from a police Crown Vic is the one you want, but you will need adapter universal joints. If you are changing ratios, plan on a new tone ring. I would rebuild the whole rear if I were going to swap in a used one. Get the best quality parts you can afford. US made parts are about the same price as Chinese, or made in India. Replace the axles, bearings and seals. Moser makes nice reasonably priced parts. Get a rebuildable LSD, or an Eaton True Trac. It will cost you $800-1000 to rebuild it. Some of the early 9C1s have 3.42 gears (GU5 on the SPID). If you find one of those, you should still replace the axles and bearings. Check the posi for operation. I believe it should take 50 lb ft of torque to make it slip.
A wagon axle would limit your tire size, or require a much greater wheel offset (30mm) to get the wheel properly positioned under the.car. The other adaptions would also apply.
I thought posting Navy Lifer's documented dimensions, then highlighting the problem ones in RED would be enough.(Post#7)
If nobody has noticed the OP has not logged onto the site since post #6.
Other participants in this thread might ask themselves if this is a case of "trolling" as the stickies on this forum, carparts dot com or a local used parts seller would give the same answer: for a unmodified direct swap sedan axles and wagon axles are considered different by GM.
Forum members may want to consider advice to new members. Some people may not have the skills to modify parts. Not every one had decades of knowledge and know what questions to ask.
As usual forum members have posted some great information and pictures that may attract a future search engine to good information.
If nobody has noticed the OP has not logged onto the site since post #6.
Other participants in this thread might ask themselves if this is a case of "trolling" as the stickies on this forum, carparts dot com or a local used parts seller would give the same answer: for a unmodified direct swap sedan axles and wagon axles are considered different by GM.
Forum members may want to consider advice to new members. Some people may not have the skills to modify parts. Not every one had decades of knowledge and know what questions to ask.
As usual forum members have posted some great information and pictures that may attract a future search engine to good information.
Welcome to the forum!
I don't have the measurements in front of me, but I can tell you that there is a very good chance that the flange bolt pattern is the same. GM has a tendency to do that, especially back in the day.
If I were you, I would be more concerned with making sure that the axle will physically bolt up to the suspension on your Olds. If any fabrication is required, then that will be a bigger obstacle than the caliper brackets.
I have two Fleetwood axles, and I only need one of them. It's the same as the wagon axle, but narrower. If you determine that it would work for you, I could sell you an axle for cheap. I'm located in northern Illinois.
Otherwise, I would say check the junkyard database on car-part.com and see if you can find a wagon axle near you.
EDIT: Just remembered that the flange bolt pattern is slightly different between sedan and wagon. My apologies. I don't want to give you any bad info. Regardless, my original statement is still accurate: there's a good chance that one of these flange bolt patterns will match what you need.
Also worth noting: the commercial Fleetwood chassis (limo/hearse) used a 9.5", 14 bolt rear. Many of them came from the factory with a 3.42 locker, but I believe some of them used a 2.93 open carrier. It's actually pretty easy to find these in junkyards. There isn't a huge market for old limos and hearses, so most of them end up being parted out.
I don't have the measurements in front of me, but I can tell you that there is a very good chance that the flange bolt pattern is the same. GM has a tendency to do that, especially back in the day.
If I were you, I would be more concerned with making sure that the axle will physically bolt up to the suspension on your Olds. If any fabrication is required, then that will be a bigger obstacle than the caliper brackets.
I have two Fleetwood axles, and I only need one of them. It's the same as the wagon axle, but narrower. If you determine that it would work for you, I could sell you an axle for cheap. I'm located in northern Illinois.
Otherwise, I would say check the junkyard database on car-part.com and see if you can find a wagon axle near you.
EDIT: Just remembered that the flange bolt pattern is slightly different between sedan and wagon. My apologies. I don't want to give you any bad info. Regardless, my original statement is still accurate: there's a good chance that one of these flange bolt patterns will match what you need.
Also worth noting: the commercial Fleetwood chassis (limo/hearse) used a 9.5", 14 bolt rear. Many of them came from the factory with a 3.42 locker, but I believe some of them used a 2.93 open carrier. It's actually pretty easy to find these in junkyards. There isn't a huge market for old limos and hearses, so most of them end up being parted out.
Hi Caddylack, there seems to be a lot of guys in your area with parts I’m interested in. Let me do some research on the fleetwood axle and see what I come up with.
Thank you Caddylac & 95wagon for the swift replies. I’m in Houston 77429 area code. I’ve used Fastenal store to store pallet shipping in the past for large items such as rear ends. Hoping if a proper rear can be sourced the seller is in proximity to a Fastenal store. I don’t think they are in all states yet.Could be worse, you could trying to buy parts for a W27
I should be able to get you most of the pertinent numbers you are looking for.
I was quite involved with a rear disc setup ( a few actually) involving the wagon housing which has that housing flange pattern.
edit to answer Caddylack, that flange spacing I think you will find is wagon specific in our years. ( discounting Limo which I have no first hand info)
The accessible housing with the stock standoff dia ( your #5 in dia) is at home so I cant get that number till later.
Where are you located?
W27 is indeed rare so I understand the struggle. I’m persistent and resourceful which is the name of the game when hunting stuff down which I’m sure you are as well. The GM B body 71-76 is a hodgepodge of different rear ends across the BOP lineup. None will interchange and it’s just a mess. Not sure what the engineers were thinking.
I definitely appreciate any info you can provide which will help streamline my search. If I can ever be of any assistance I am always willing. Ultimately, I am hoping to find something with a 3.42 posi and matching axle flanges which sounds like a wagon. I’ll be running a 4l85 so this ratio will be perfect for 1st gear as well as .7 overdrive.
I am not well versed on the wagon rears are they bolt in axles? I believe some of the early 9C1 had the 3.42 posi but not sure if wagons ever had a police/taxi option. I’m sure this is like asking for help finding hen’s teeth.
Could be worse, you could trying to buy parts for a W27 
I should be able to get you most of the pertinent numbers you are looking for.
I was quite involved with a rear disc setup ( a few actually) involving the wagon housing which has that housing flange pattern.
edit to answer Caddylack, that flange spacing I think you will find is wagon specific in our years. ( discounting Limo which I have no first hand info)
The accessible housing with the stock standoff dia ( your #5 in dia) is at home so I cant get that number till later.
Where are you located?
I should be able to get you most of the pertinent numbers you are looking for.
I was quite involved with a rear disc setup ( a few actually) involving the wagon housing which has that housing flange pattern.
edit to answer Caddylack, that flange spacing I think you will find is wagon specific in our years. ( discounting Limo which I have no first hand info)
The accessible housing with the stock standoff dia ( your #5 in dia) is at home so I cant get that number till later.
Where are you located?
Unfortunately. these are all C lock
The 92-96 wagons are corp 8.5 ten bolts with 30 spline
The mid late 70 Chev wagons were C lock corp ( I called them 8.875 but I think Gm was 8.75) the bastard 12 bolt ring gear in big 10 bolt housing.
The one huge thing about the corp 8.5 is parts but in a chev, always going to be C lock .
Smattering of BOP bolt in in "A" bodys as you know but same tube narrow stuff
The 92-96 wagons are corp 8.5 ten bolts with 30 spline
The mid late 70 Chev wagons were C lock corp ( I called them 8.875 but I think Gm was 8.75) the bastard 12 bolt ring gear in big 10 bolt housing.
The one huge thing about the corp 8.5 is parts but in a chev, always going to be C lock .
Smattering of BOP bolt in in "A" bodys as you know but same tube narrow stuff
All it takes is money
I bucked the ends off and did bolt in 33 spline
post 155 on
www.impalassforum.com
The limo diff is stronger with stock 33 but still a C lock.
All that said, the weak point is the stock axles, I am at 4500 pounds , a stick, 13.7 overall first gear.
On slicks, they twist , but the rest of the diff is pretty stout.
This why I am moving to 33
I bucked the ends off and did bolt in 33 spline
post 155 on
95wagon LS7 project
Before the forum crash, Gerry was talkin' about dropping an LS7 in his spotless wagon. Anyone else here itchin' for a project update???
www.impalassforum.com
The limo diff is stronger with stock 33 but still a C lock.
All that said, the weak point is the stock axles, I am at 4500 pounds , a stick, 13.7 overall first gear.
On slicks, they twist , but the rest of the diff is pretty stout.
This why I am moving to 33
" I’ll be north of 1k hp to the wheels. Twin turbo LSX build "
Out of my league by nearly a factor of 2
We have a smattering a huge power guys on here running huge power levels but not at Queen Mary weights.
Reinventing the wheel might not be the route here with fabbed 9 inch and Spicer 60 housings readily available.
The above based on leaving on boost and hooking
I will still try and get you some measurments.
Out of my league by nearly a factor of 2
We have a smattering a huge power guys on here running huge power levels but not at Queen Mary weights.
Reinventing the wheel might not be the route here with fabbed 9 inch and Spicer 60 housings readily available.
The above based on leaving on boost and hooking
I will still try and get you some measurments.
Gears for a 9.375" Type O (full size) - ClassicOldsmobile.com
Drivetrain/Differentials - Gears for a 9.375" Type O (full size) - I have an anti-spin type O rear (1967 Delmont 88, 9.375 ) that is a 2.73 or 2.78 (whatever stock ratio was available near 2.75). What ring and pinions will fit in that differential? The car was recently converted to a 4 speed and...
classicoldsmobile.com
I assume you know Jim at JD Race ??
Gears for a 9.375" Type O (full size) - ClassicOldsmobile.com
Drivetrain/Differentials - Gears for a 9.375" Type O (full size) - I have an anti-spin type O rear (1967 Delmont 88, 9.375 ) that is a 2.73 or 2.78 (whatever stock ratio was available near 2.75). What ring and pinions will fit in that differential? The car was recently converted to a 4 speed and...
classicoldsmobile.com
From an overall fitment perspective, the info below (and from others earlier in the same thread) might be helpful?
www.impalassforum.com
In summary - the wagon rear ends are functionally 1/2 ton truck rear ends with control arms instead of leaf springs
The commercial chassis rear ends are functionally heavy 3/4 ton truck rear ends with control arms instead of leaf springs
1000 HP, sticky tires, heavy car, good chassis setup will kill either one of these on a hard dragstrip launch.
Rearend Widths
I'm not sure if this belongs here, in wheels and tires, exterior, or suspension. Can we get a list of what the rear ends are and what widths are? I know it used to be on here but I searched some and I think it's gone. I'd like to know the widths for the drum, Civie Disc (did those exist?)...
www.impalassforum.com
In summary - the wagon rear ends are functionally 1/2 ton truck rear ends with control arms instead of leaf springs
The commercial chassis rear ends are functionally heavy 3/4 ton truck rear ends with control arms instead of leaf springs
1000 HP, sticky tires, heavy car, good chassis setup will kill either one of these on a hard dragstrip launch.
Appreciate the summarization, it makes a lot of sense. I’ll have to end up going with one of these options in the short term and limit boost to a “reasonable” level. The axle flange on the commercial rear makes it a front runner in my mind allowing me to use my 4 piston disc brake brackets. When I do eventually get a proper rear end, crank the boost and let it rip tater chip 🏁
As an aside, my son will be a month old on Thursday. I’m juggling helping the wife who had a C section and doing research on this subject while I’m off work. Trying to cram it in while I have time as that’s now my most valuable commodity. Hopefully I can decide on something soon and move forward. I have not had time to check the website mentioned to me above for junkyard stock in the Houston area. But I will tonight when everyone is asleep.
As an aside, my son will be a month old on Thursday. I’m juggling helping the wife who had a C section and doing research on this subject while I’m off work. Trying to cram it in while I have time as that’s now my most valuable commodity. Hopefully I can decide on something soon and move forward. I have not had time to check the website mentioned to me above for junkyard stock in the Houston area. But I will tonight when everyone is asleep.
Near as I can measure.
.439 bolt holes 7/16 shank bolts as a close fit. The car uses
SAE shoulder bolts as the hole in the backing plate is larger than
the housing register. Not much but enough it doesn't center the backing
plate.
Looking back at old notes, I have machined part of the housing
register as incredibly short and 3.18 . It has a very big radius.
I noted that you would have to be about 3.2 to clear this radius if
you didn't relieve the hole.
Near as I can measure right now I am seeing
3.771 across the top centers
2.991 across the bottom center
2.481 top to bottom centers
The axle is still in and these numbers may be scewed.
2.415 looks to be front of backing plate flange to outside of axle
flange. ( Bill has stated 2.375 in some emails)
That was derived from back of flange to back of
flange 2.337 minus housing flange - .290 plus shaft
flange + .368 = 2.415
.439 bolt holes 7/16 shank bolts as a close fit. The car uses
SAE shoulder bolts as the hole in the backing plate is larger than
the housing register. Not much but enough it doesn't center the backing
plate.
Looking back at old notes, I have machined part of the housing
register as incredibly short and 3.18 . It has a very big radius.
I noted that you would have to be about 3.2 to clear this radius if
you didn't relieve the hole.
Near as I can measure right now I am seeing
3.771 across the top centers
2.991 across the bottom center
2.481 top to bottom centers
The axle is still in and these numbers may be scewed.
2.415 looks to be front of backing plate flange to outside of axle
flange. ( Bill has stated 2.375 in some emails)
That was derived from back of flange to back of
flange 2.337 minus housing flange - .290 plus shaft
flange + .368 = 2.415
Ok, to clarify
I am measuring the welded housing flange where the backing plate touches down to axle flange where the rotor touches down.
I stand by my 2.4ish measurement.
I am measuring the welded housing flange where the backing plate touches down to axle flange where the rotor touches down.
I stand by my 2.4ish measurement.
Attachments
The sedan and most 10 and 12 bolt car have a 2.812 stand off.
Typical ford and mopar is 2.5
The wagon is a shallow 2.4ish
Your 2.105 number is confusing to me.
The red ring in the cad drawing, it is ?
Are you measuring from the outside of your brake adapter ?
Typical ford and mopar is 2.5
The wagon is a shallow 2.4ish
Your 2.105 number is confusing to me.
The red ring in the cad drawing, it is ?
Are you measuring from the outside of your brake adapter ?
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