Drove to Florida this past week for vacation and started looking around on craigslist for camaro parts, found a decent 3.73 LS disk rear end, just needs to be cleaned up, new fluid etc. So I'll be picking it up on my way back home next week.

So, my rear end is a drum setup. What will I need for the switch? Ebreak cable, break line fittings? What?

Any info would be greatly appreciated.

 

this is a 4th gen rear? you will need custom brake cables (hawks or flynbye) and adapters or something to convert to your brake lines, since you shoudl ahve SAE flares and the later rear will have bubble flares.

you should use a disc/disc prop valve or an adjustable one to get the most out of the brakes

 

No, sorry forgot to mention. Its out of an 84 TA

 

The following will answer most of your questions, I think:

https://www.thirdgen.org/forums/tran...-10-bolts.html

Oh, if you can, compare your combination valve with the one in the donor car. If they 'look' the same (iron), take it. Finding an old style disc/disc valve might be somewhat difficult. More info about valves above.

JamesC

 

Thank you! I looked all over for a sticky on this stuff but couldn't find it.

Now it talks about switching the proportional valve and Ebreak cables when using a newer rear-end with a older car, but both my car and the rear I am gonna put in it are 84's, so I wonder if I'll still need to do that....

 

Yes. The bias is different between drum and disc rears. The parking brake cables are different.

If I Swap From a Drum to a Disc Rear End Do I Have to Change the Combination Valve?*
Yes, for the best brake performance. Use a standard disc brake valve for 82-88 swaps.

If I Swap to a Disc Rear End Will My Parking Brake Work?
Yes. For 82-88 cars simply buy the correct application. For example, if the rear is from an 88, order disc brake cables for an 88.


JamesC

 

Thanks for the info, it was unclear to me.

Your always a help James!

 

If you have drum brakes now, you'll have to change the MC and PV to downgrade to the cast-iron Saginaw brakes that basically don't work.

Odds are, the posi in it is an Auburn, and is worn out. Auburn does not offer service parts for those so once they go bad they are junk.

Personally, I'd suggest passing on it, and keeping your eyes open for a 90-up disc/posi unit instead. That'll have the better disc brakes (ones that actually WORK!!) and 28 spline axles, which makes it easier to get good posi units to replace the Auburn garbage.

You'll also find that your drum PV and MC will work acceptably well with the 90-92 brakes, and the parking brake cables on those will hook right up to your existing system as if they were meant to. An altogether better swap.

 

I've still gotta check it out and make sure what condition it is. My first thought was going with a 4th gen SS rear. But, I found this for a great deal so was giving it some thought.

 

According to GM in the above link, there's no need to swap the MC. Could be that the LS is an Eaton (which is nothing to write home about either).

JamesC

 

From what I've read you don't HAVE to replace the MC. You can if you want, to decrease the amount of breaking pressure you actually put into the break pedal.

Like, I said, still waiting to hear back from him about details. Auburn or Eaton no idea as of right now.

 

The J65 brake system was designed with a low pedal ratio for reduced free travel and a firmer and higher effort pedal for the high performance buyer. Owners of J65 equipped Camaro cars not sharing this interest and desiring reduced brake pedal effort can be accommodated by replacing the original production master cylinder assembly with the appropriate J50 [drum] master cylinder unit specified below.

I wouldn't both with it myself.

JamesC

 

Definitely don't plan on it.

Alright, heard back from the guy. He is going to decode the serial number to try and find out more info but here it was we have

Pulled off a 84 TA
Posi
3.73 gears
disk breaks
He has the proportional disk/disk valve.
Comes with sway bars and the such
Doesn't have the e-break cables

He has no idea how many miles are on it, but he said it was working like a dream with no noises when it was pulled. He thinks that the rotors might be shot, and said he would probably get them replaced.

All in all he wants $150 for it.

What do you think?

 

For that price, might be an OK risk.

Not having the praking brake cables could be a PITA, since that brake system ABSOLUTELY 100% POSITIVELY WILL NOT work for more than a few hundred miles without them. They are not quite "self-adjusting", like we all think of disc brakes as being; instead, the act of operating the parking brake adjusts them by sort of unscrewing the piston to make it "taller". Meaning, if you don't use it, they work less and less as they wear, until they basically stop doing anything at all, which doesn't take real long. So, make sure you can get the cables, and if so, it'll be something workable.

 

Looked online last night and found some e brake cables for about $15/shipped. And then rotors run about $30-50ea. So in the end i've spent around $250