LS1 rear brakes - tips & tricks

doublejack · 08-18-2005, 04:23 PM

Over the past couple of weeks I've been doing some upgrades on my truck. The Zexel Torsen posi unit is in, the battery is being relocated from under the hood to under the bed (it'll be mounted where the spare tire used to be), and I installed 12" rear disc brakes from a LS1 Camaro / Firebird. I'm also stripping the frame and coating it in POR-15 since I have the bed off.

The reason for this post is to share what I learned doing this project while it's fresh in my mind. In particular about the brake conversion. Installing the brakes was not that difficult but it was the hardest part of the project. I know there have been many threads on the subject because it's a popular swap, so I'm not going to rehash what has already been covered. However, there is some confusing or conflicting info and I will try to clear a little of that up. I'll also cover a couple points that I didn't read about in other threads before I tackled the project.

1. The brake setup is pretty much a bolt-on deal (except the e-brakes, more later). The basic parts needed include backing plates, caliper brackets, calipers, flexible brake lines that bolt to the calipers, and a set of brake pad retaining clips. New pads & rotors is a good idea if you bought a used take-off system.

2. You will need adapters to connect the S10's hard brake lines to the flex lines that bolt to the calipers. The adapter is needed because the S10's hard lines have a standard double flare end, while a Camaro's hard lines have a rounded flare end. So you need a standard double flare to rounded flare adapter for each side.

Of course there are other options (re-flare the ends, mod a Camaro's hard lines to fit, etc.) but these adapters are cheap so I highly recommend that route. I paid $2 a piece at the local auto parts store. Note that you can physically connect the S10's hard line to the Camaro flex line without the adapter because the threads are identical, but if you do that there is a good chance a leak will develop (immediately or eventually) because the flare isn't the proper type for the fitting on the flex line. It just won't seal properly and sooner or later the pressure is going to make it fail.

3. When bolting the backing plates to the flange on the end of the axle tube, many S10 owners will need to use washers for spacers, but not everyone. There has been some debate and conflicting info on this point. Well, I know why.

There are two different rear end housings that went into S10's. They are very close to the same, but are not identical. One is made in Canada and the other in the US. They take all the same parts (carrier, carrier bearings, carrier bearing races, axles, axle bearings, etc.) *EXCEPT* the axle tube seals. They have a minor difference right at the end of the tube and this is why they require different seals. The seals for one rear housing have a slightly larger diameter than the other. So when you go to buy new seals, take one of your old ones to the store to make sure you get the right ones.

Now, if you get lucky then you won't need washers because the backing plate will fit flush against the flange. But if you get unlucky, then you absolutely will need spacers. I don't know if I have the US or Canadian housing, but I needed washers on mine. There was a small ridge on the axle tube, maybe 1/8" tall and slightly less than that in thickness. This ridge was right up agsint the flange (it's purpose is probably to locate the flange on the tube in the manufacturing process). The center hole on the brake backing plate was not large enough to clear this ridge, so it would not go flush against the flange.

At first I tried to mount the backing plate without using washers, but it proved impossible to get it square. When I mounted the caliper it was at an agle to the rotor, and the rotor wouldn't turn as a result. I used thick washers (about 1/8") which were slightly thicker than the ridge and that alleviated the alignment problem.

4. If you want or need emergency brakes be prepared to do some labor and get creative. Camaro e-brake cables won't work on a S-10 because they are the wrong length. I found advice that suggested using newer Blazer 4x4 cables. They are the correct length but there are a few challenges:

A. The Blazer and Camaro e-brake actuators work the same way. A lever on the backing plate hooks a slot on the end of the cable. However, the lever on the Camaro is much fatter than the Blazer's is. So, to get the cable to work with the LS1 lever you have to grind away a good chunk of the lever (make it thinner, not shorter) and also grind on the cable end to open up the slot using a dremmel tool and a small grinding bit. The best idea is to take material from both the lever & cable end so neither will become too weak and break on you.

B. You'll have to either heavily modify a Camaro's e-brake cable mounting brackets, or fab up your own from scatch to get the e-brakes working. The reason is that Blazers don't have a bracket, the mounting point for the cable is built into the backing plate itself. And Camaros don't have leaf springs, so their bracket doesn't mount to an S-10's rear end housing.

To solve this I drilled a hole in the front of each leaf spring perch, and I hacked away 60-70% of a Camaro bracket. Then I drilled a hole in each of the Camaro brackets to line up with the ones in the perches in such a way that the cables were positioned correctly to actuate the lever. I finished by bolting them on using a 1.5" long 10mm bolt and nut. It doesn't look stock, but it's functional and that's all I cared about. You can't see it unless you crawl under the truck anyway. Sorry, no digital camera so I can't post pics.

C. When you are adjusting the e-brake cables there is something very important to consider - rear end travel. You can not just have the vehicle at rest height (like parked on a level surface), adjust the e-brake and think it's fine. That won't work.

For example, it would be very bad if the e-brake locked up the rear wheels at full shock extension. If that happened you could go over a big bump in the road and when your rear tires land initially they wouldn't turn. They would skid until the rear end retracted enough to allow some slack in the cables.

It would be equally as bad if the lines were adjusted in a way that you had no e-brake when the shocks were at maximum compression. Like if you loaded the bed with a yard of gravel and it was sagging real low, if the cables aren't set just right there may not be enough travel in the e-brake pedal to engage the brakes.

What you have to do is use a jack and jackstands to simulate these conditions and verify that your e-brakes work correctly at all points. It will only take a few extra minutes but it's a step I haven't seen anyone mention when doing this conversion.

5. Wheel clearance - I have a 99 LS with the stock 15" wheels. They are aluminum 5 spoke two-tone, kind of grayish on the insets of the spokes and polished aluminum look on the rest of the wheel. The wheels did clear the rear brake setup but it was really, really close. I ended up taking a grinder to the calipers and caliper mounting brackets to give myself more clearance. I didn't take a lot off, just enough to feel safe.

I removed material that was close to the spokes as well as the inside of the wheel, like the very corners of the caliper brackets and the raised area on the caliper near the top-center of the outer pad. I trimmed the caliper's cooling fins just a tad as well. Some 15" wheels clear without any grinding required, and some 15" wheels won't clear at all. It just varies. If you do have to grind, be careful not to over-do it or you'll end up with scrap.

Hope this helps those who take on this conversion. I feel it is definitely worthwhile and it really isn't that difficult, but now you know the little tricks needed to get the job done right. If anyone has questions feel free to PM me, but be aware that it sometimes takes a few days for me to get back with people. I don't have a digital camera at the moment so no pics yet, but I'll pick one up over the weekend and snap some shots before I put the truck back together if people are interested.

DfntPntbll · 08-18-2005, 05:24 PM

Holy long post batman,.... I am gonna keep track of this thread,... looking to do the corvette brakes sometime,... good luck

s10blaza · 06-12-2006, 03:47 AM

This is a great post. I have one question though, did the brakes push out the tire farther out than the old drum brakes? Its a pretty important issue for me since I'm bodydropped and rims I have literally rub against the rear quarter panel laid out.

98 Pewter Sonoma · 06-12-2006, 07:42 PM

Quote: Originally Posted by doublejack

I don't have a digital camera at the moment so no pics yet, but I'll pick one up over the weekend and snap some shots before I put the truck back together if people are interested.

That would be great!

s10cyncrvr · 06-13-2006, 09:36 AM

Good info, thanks for sharing.

gregoneck · 07-21-2006, 10:30 AM

well this is an old ass thread but do have to use v8 camaro or firebird parts or do v6 cars have the same brake set up? all that is ever said is ls1 or lt1. just curious.

smitty64 · 07-22-2006, 12:49 AM

You just want 98+ v8 or v6. The lt1s have smaller brakes.

gregoneck · 07-23-2006, 11:25 AM

Quote: Originally Posted by smitty64

You just want 98+ v8 or v6. The lt1s have smaller brakes.

good to go. thanks for the info.

08-18-2005, 04:23 PM	#1
doublejack Registered User Age: 33 Join Date: Apr 2004 Posts: 230 Location: Detroit User is: OffLine	LS1 rear brakes - tips & tricks Over the past couple of weeks I've been doing some upgrades on my truck. The Zexel Torsen posi unit is in, the battery is being relocated from under the hood to under the bed (it'll be mounted where the spare tire used to be), and I installed 12" rear disc brakes from a LS1 Camaro / Firebird. I'm also stripping the frame and coating it in POR-15 since I have the bed off. The reason for this post is to share what I learned doing this project while it's fresh in my mind. In particular about the brake conversion. Installing the brakes was not that difficult but it was the hardest part of the project. I know there have been many threads on the subject because it's a popular swap, so I'm not going to rehash what has already been covered. However, there is some confusing or conflicting info and I will try to clear a little of that up. I'll also cover a couple points that I didn't read about in other threads before I tackled the project. 1. The brake setup is pretty much a bolt-on deal (except the e-brakes, more later). The basic parts needed include backing plates, caliper brackets, calipers, flexible brake lines that bolt to the calipers, and a set of brake pad retaining clips. New pads & rotors is a good idea if you bought a used take-off system. 2. You will need adapters to connect the S10's hard brake lines to the flex lines that bolt to the calipers. The adapter is needed because the S10's hard lines have a standard double flare end, while a Camaro's hard lines have a rounded flare end. So you need a standard double flare to rounded flare adapter for each side. Of course there are other options (re-flare the ends, mod a Camaro's hard lines to fit, etc.) but these adapters are cheap so I highly recommend that route. I paid $2 a piece at the local auto parts store. Note that you can physically connect the S10's hard line to the Camaro flex line without the adapter because the threads are identical, but if you do that there is a good chance a leak will develop (immediately or eventually) because the flare isn't the proper type for the fitting on the flex line. It just won't seal properly and sooner or later the pressure is going to make it fail. 3. When bolting the backing plates to the flange on the end of the axle tube, many S10 owners will need to use washers for spacers, but not everyone. There has been some debate and conflicting info on this point. Well, I know why. There are two different rear end housings that went into S10's. They are very close to the same, but are not identical. One is made in Canada and the other in the US. They take all the same parts (carrier, carrier bearings, carrier bearing races, axles, axle bearings, etc.) EXCEPT the axle tube seals. They have a minor difference right at the end of the tube and this is why they require different seals. The seals for one rear housing have a slightly larger diameter than the other. So when you go to buy new seals, take one of your old ones to the store to make sure you get the right ones. Now, if you get lucky then you won't need washers because the backing plate will fit flush against the flange. But if you get unlucky, then you absolutely will need spacers. I don't know if I have the US or Canadian housing, but I needed washers on mine. There was a small ridge on the axle tube, maybe 1/8" tall and slightly less than that in thickness. This ridge was right up agsint the flange (it's purpose is probably to locate the flange on the tube in the manufacturing process). The center hole on the brake backing plate was not large enough to clear this ridge, so it would not go flush against the flange. At first I tried to mount the backing plate without using washers, but it proved impossible to get it square. When I mounted the caliper it was at an agle to the rotor, and the rotor wouldn't turn as a result. I used thick washers (about 1/8") which were slightly thicker than the ridge and that alleviated the alignment problem. 4. If you want or need emergency brakes be prepared to do some labor and get creative. Camaro e-brake cables won't work on a S-10 because they are the wrong length. I found advice that suggested using newer Blazer 4x4 cables. They are the correct length but there are a few challenges: A. The Blazer and Camaro e-brake actuators work the same way. A lever on the backing plate hooks a slot on the end of the cable. However, the lever on the Camaro is much fatter than the Blazer's is. So, to get the cable to work with the LS1 lever you have to grind away a good chunk of the lever (make it thinner, not shorter) and also grind on the cable end to open up the slot using a dremmel tool and a small grinding bit. The best idea is to take material from both the lever & cable end so neither will become too weak and break on you. B. You'll have to either heavily modify a Camaro's e-brake cable mounting brackets, or fab up your own from scatch to get the e-brakes working. The reason is that Blazers don't have a bracket, the mounting point for the cable is built into the backing plate itself. And Camaros don't have leaf springs, so their bracket doesn't mount to an S-10's rear end housing. To solve this I drilled a hole in the front of each leaf spring perch, and I hacked away 60-70% of a Camaro bracket. Then I drilled a hole in each of the Camaro brackets to line up with the ones in the perches in such a way that the cables were positioned correctly to actuate the lever. I finished by bolting them on using a 1.5" long 10mm bolt and nut. It doesn't look stock, but it's functional and that's all I cared about. You can't see it unless you crawl under the truck anyway. Sorry, no digital camera so I can't post pics. C. When you are adjusting the e-brake cables there is something very important to consider - rear end travel. You can not just have the vehicle at rest height (like parked on a level surface), adjust the e-brake and think it's fine. That won't work. For example, it would be very bad if the e-brake locked up the rear wheels at full shock extension. If that happened you could go over a big bump in the road and when your rear tires land initially they wouldn't turn. They would skid until the rear end retracted enough to allow some slack in the cables. It would be equally as bad if the lines were adjusted in a way that you had no e-brake when the shocks were at maximum compression. Like if you loaded the bed with a yard of gravel and it was sagging real low, if the cables aren't set just right there may not be enough travel in the e-brake pedal to engage the brakes. What you have to do is use a jack and jackstands to simulate these conditions and verify that your e-brakes work correctly at all points. It will only take a few extra minutes but it's a step I haven't seen anyone mention when doing this conversion. 5. Wheel clearance - I have a 99 LS with the stock 15" wheels. They are aluminum 5 spoke two-tone, kind of grayish on the insets of the spokes and polished aluminum look on the rest of the wheel. The wheels did clear the rear brake setup but it was really, really close. I ended up taking a grinder to the calipers and caliper mounting brackets to give myself more clearance. I didn't take a lot off, just enough to feel safe. I removed material that was close to the spokes as well as the inside of the wheel, like the very corners of the caliper brackets and the raised area on the caliper near the top-center of the outer pad. I trimmed the caliper's cooling fins just a tad as well. Some 15" wheels clear without any grinding required, and some 15" wheels won't clear at all. It just varies. If you do have to grind, be careful not to over-do it or you'll end up with scrap. Hope this helps those who take on this conversion. I feel it is definitely worthwhile and it really isn't that difficult, but now you know the little tricks needed to get the job done right. If anyone has questions feel free to PM me, but be aware that it sometimes takes a few days for me to get back with people. I don't have a digital camera at the moment so no pics yet, but I'll pick one up over the weekend and snap some shots before I put the truck back together if people are interested.
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08-18-2005, 05:24 PM	#2
DfntPntbll Registered User Age: 25 Join Date: Feb 2003 Posts: 4,062 Location: St. Auggie Dog, Florida User is: OffLine	Re: LS1 rear brakes - tips & tricks Holy long post batman,.... I am gonna keep track of this thread,... looking to do the corvette brakes sometime,... good luck
	[Reply w/Quote]

06-12-2006, 03:47 AM	#3
s10blaza CHANGE YOUR EMAIL ADDRESS Age: 25 Join Date: Jan 2003 Posts: 1,347 Location: El Paso, TX User is: OffLine	Re: LS1 rear brakes - tips & tricks This is a great post. I have one question though, did the brakes push out the tire farther out than the old drum brakes? Its a pretty important issue for me since I'm bodydropped and rims I have literally rub against the rear quarter panel laid out.
	[Reply w/Quote]

06-12-2006, 07:42 PM	#4
98 Pewter Sonoma Working Hard at Life Age: 28 Join Date: Jul 2003 Posts: 876 Location: Knoxville, TN User is: OffLine	Re: LS1 rear brakes - tips & tricks Quote: Originally Posted by doublejack I don't have a digital camera at the moment so no pics yet, but I'll pick one up over the weekend and snap some shots before I put the truck back together if people are interested. That would be great!
	[Reply w/Quote]

06-13-2006, 09:36 AM	#5
s10cyncrvr Canyon Carver Age: 29 Join Date: Jul 2004 Posts: 2,852 Location: Columbia, IL User is: OffLine	Re: LS1 rear brakes - tips & tricks Good info, thanks for sharing.
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07-21-2006, 10:30 AM	#6
gregoneck child at heart Age: 36 Join Date: Feb 2005 Posts: 1,500 Location: DFW User is: OffLine	Re: LS1 rear brakes - tips & tricks well this is an old ass thread but do have to use v8 camaro or firebird parts or do v6 cars have the same brake set up? all that is ever said is ls1 or lt1. just curious.
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07-22-2006, 12:49 AM	#7
smitty64 Registered User Age: 21 Join Date: Apr 2005 Posts: 102 Location: User is: OffLine	Re: LS1 rear brakes - tips & tricks You just want 98+ v8 or v6. The lt1s have smaller brakes.
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07-23-2006, 11:25 AM	#8
gregoneck child at heart Age: 36 Join Date: Feb 2005 Posts: 1,500 Location: DFW User is: OffLine	Re: LS1 rear brakes - tips & tricks Quote: Originally Posted by smitty64 You just want 98+ v8 or v6. The lt1s have smaller brakes. good to go. thanks for the info.
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