3rd gen - 4th gen rear swap

[Jersyboyy]

I currently have on the car a drum thirdgen rear.
I have in my garage a 99/00 z28 rear with 3:42s with brakes but no brake lines.

Would the brake lines from the old rear work on the 4th gen rear?
Do I need to go to a junkyard and pull brake lines for a 4th gen rear instead or what?

I already got the disc/disc prop valve, and using 4th gen wheels. Is their anything else I need?

[WildBillyT]

If I remember correctly, the new rear is 2" wider than the old one so it might not reach. You don't want to take bends out of it if you can avoid it.

If you want to you can go to NAPA and get bulk brake line and make your own if you have access to a tubing bender and a flaring tool... but you have to do a 100% awesome job, no "that's good enough" like some guys do. Also, you can't use a compression union to join the lines, no matter what people might tell you. It fits and can hold a little pressure but won't last, and it's illegal anyway.

[91DropTop]

just buy new lines...you dont wanna take a chance with brakes, you have a hard enough time keeping your wheels on the car, dont be cheep!

[Jersyboyy]

bending and flaring no problem but how much tubing would I need for each side. Does the brake lines go from the front of the car ALL the way to the rear or is their a junction in the middle some where, and wouldnt that junction be similar to a compression union?

If I choose to do my own brake lines would I have to bend fit and put the brake lines on first before I swap the rear or can I swap it and do the rest later?

[WildBillyT]

Originally Posted by Jersyboyy

bending and flaring no problem but how much tubing would I need for each side. Does the brake lines go from the front of the car ALL the way to the rear or is their a junction in the middle some where, and wouldnt that junction be similar to a compression union?

If I choose to do my own brake lines would I have to bend fit and put the brake lines on first before I swap the rear or can I swap it and do the rest later?

Tubing is really cheap. I'd get a lot extra though, in case some flares don't turn out right. I can't stress enough that you have to strive for perfection.

You do not need to swap all of the lines on the car. There should be a flex hose back by the rear axle that acts as a union between two halves of the brake line going to the rear wheels. Pop under the car and you will see what I mean. You should only have to replace the two brake lines on the rear axle.

Have a look at these vids:

http://www.ehow.com/video_2328133_to...ake-lines.html

I don't think you will need the torch, though.

[Jersyboyy]

Thanks wildbilly ill get to work on it tomorrow and maybe have the rear swapped this weekend!!! Ill keep you guys updated!

[WildBillyT]

Originally Posted by Jersyboyy

Thanks wildbilly ill get to work on it tomorrow and maybe have the rear swapped this weekend!!! Ill keep you guys updated!

Yeah, I've done it a few times, it's not that hard. BUT MAKE SURE YOU GET GOOD FLARES.

Good luck to ya.

[//<86TA>\\]

im not totally positive on this, but here is an observation.

I swapped the ls1 rear brakes onto my 3rd gen that originally had drums brakes. With the discs, you need to use flex lines to the calipers. My stock drum brake lines were so long that i had to put loops in them to match them up with the new flex lines. While this was done on a 3rd gen width rear, not the wider 4th gen one, you might luck out and not have to make new lines. Provided your stock lines dont break when you take them off, you might be able to just re-bend them a little and make them work.

Something to check before you buy a flaring tool and lines.

You wouldnt happen to have the brake lines from your 4th gen rear would you? because they will bolt right up to your existing flex line from the chassis.

[Jersyboyy]

The 4th gen rear I got came with everything EXCEPT the brake lines. Sucks I know but 300 with calipers rotors pads and all was too good of a deal to pass up over some brake lines.

[WildBillyT]

Originally Posted by //<86TA>\\

im not totally positive on this, but here is an observation.

I swapped the ls1 rear brakes onto my 3rd gen that originally had drums brakes. With the discs, you need to use flex lines to the calipers. My stock drum brake lines were so long that i had to put loops in them to match them up with the new flex lines. While this was done on a 3rd gen width rear, not the wider 4th gen one, you might luck out and not have to make new lines. Provided your stock lines dont break when you take them off, you might be able to just re-bend them a little and make them work.

Something to check before you buy a flaring tool and lines.

You wouldnt happen to have the brake lines from your 4th gen rear would you? because they will bolt right up to your existing flex line from the chassis.

Phil, you are right.

JB-

You need flex lines for your calipers. I mis-posted above. Serves me right for posting after a 12 hour day. Sorry. The stuff is still applicable for making hard lines but isn't quite right for your app now.

[Jersyboyy]

The flex lines can be bought at local auto parts store right? Or should I pull them off at the junkyard tom? So hardlines to flex lines to calipers right?

[Tru2Chevy]

Do yourself and the other drivers on the road a favor and buy new flex line from the parts store.

- Justin

[IROCdan330]

dont forget to:

a. get a prop valve from a disc rear third gen or
b. get an adjustable prop valve from jegs, summit, etc.

otherwise your rear brakes MAY not work.

As far as the junction for the 2 lines going each way, there is a little block that has the 1 line from the front going into it and it has 2 outs on its sides. It bolts to the diff area. This can be swapped from your rear to the new one.

[Teds89IROC]

I did a 4th gen swap; I had to pick up 4th gen e-brake lines to work with the additional length of the 4th gen rear. While you're buying lines, I'd also pick up new rubber brake hoses that go from the calipers to the hard lines. They deteriate inside over time and block the fluid from moving freely which will end up warping your rotors and wearing out your pads rather quickly.

[Jersyboyy]

ok guys im buying new tblock and flex lines from the calipers, as far as the hardlines go I can just buy my own hardline and make my own flares since the rear I got has none right?

& ted do you know the part number for the correct 4th gen ebrake cables, if I remember correctly people had trouble with one set of cables vs's the other.

[WildBillyT]

Originally Posted by Jersyboyy

ok guys im buying new tblock and flex lines from the calipers, as far as the hardlines go I can just buy my own hardline and make my own flares since the rear I got has none right?

& ted do you know the part number for the correct 4th gen ebrake cables, if I remember correctly people had trouble with one set of cables vs's the other.

JB:

Yes. I JUST did this for my 9". You can buy preflared lines from your local auto store, and if you are careful you may not have to flare anything.

[Teds89IROC]

unfortunately I don't, I did this swap years ago. I knew the year and model of the car the rear came from so I ordered the lines that way.

[//<86TA>\\]

Originally Posted by WildBillyT

JB:

Yes. I JUST did this for my 9". You can buy preflared lines from your local auto store, and if you are careful you may not have to flare anything.

and make sure you get "bubble flare" not "double flare" or "inverted flare"

[WildBillyT]

Originally Posted by //<86TA>\\

and make sure you get "bubble flare" not "double flare" or "inverted flare"

Yes, they should sell different types in diffrent lengths.