Hello!
I bought an 84 about a year ago to drive/wheel while fixing my 83. Since then I've developed some braking issues on the front.
The previous owner said that him and his brother did a vented rotor / larger caliper mod at some point. But he didn't remember which way they went about doing it (said his brother just showed up with the parts).

Now that I need to do some work on the brakes that is turning out to be a pain. I've never done the mod myself but I've heard / read that there are multiple possible ways to do this mod and if I remember correctly some even involve swapping over to IFS hubs.

Can anyone identify which calipers and rotors these are?
Also, I doubt he swapped to IFS hubs and these look to be the same as my 83 SFA hubs but I haven't had an opportunity to measure them against each other yet and it may be a minute before I could get to the 83 to do so. Does anyone have a suggestion of an easy way to spot IFS hubs swapped to a SFA? I've never had an IFS truck so not sure what to look for.

Thanks in advance for any help,

Sam


Whole assembly with 2" spacer attached, PO removed the rock guards.



Caliper outside



Caliper back (I know, the clip was dragging)



Caliper inside



Caliper stamp



Rotor thickness



Rotor hub attachment / measurement



What a great helper...haha

 

The typical swap back then was to just use the V6 (3.0) calipers and rotors. Your hubs are just the straight axle hubs with a spacer. The IFS hubs put the wheel mounting surface out further. I just looked up an 88 pickup with the 3.0 on Rock auto and they show the calipers you have. Casting S12W. They list the rotor specs so you'll have to look. The spacer is typically a 1.5" on each side to match the width of the IFS width rear axles when the IFS guys do a SAS.

The most recent brake upgrades are going to IFS hubs to get rid of the spacers and go to a slip on rotor. Check out Sky's or Front Range Off Road for the kits and info.

I just did the big brake upgrade using one of these kits and I ran into some problems so PM me if you decide to go this route. Some options require larger wheels so be aware of that as well.

I hope this helps. Good luck with your trucks.

 

IFS rotors dont work on SA axles (different hat depth) , but the calipers do.

That looks like a FJ60 rotor.

 

Thanks for the replies! This helps a lot.

So it looks like I'm looking at 3.0 calipers and FJ60 (or I've heard 40 also?) rotors then. This jives with one of the methods I've heard about. Thanks for the confirmation. I'll measure the rotor to be sure.

AZ: Yeah, I put the 2" spacers on to get the rim to clear the caliper. The PO had done some sketchy spacing to get the rim to clear (and just barely at that) that left the lug/nut thread engagement much less than I would like. See pics:


Spacer



Not much lug there



Dang that's close!

 

Yep, Rattlewagon is right about the rotors. It's all coming back to me. Years ago I ended up putting T100 calipers and rotors on mine and a dual diaphragm booster from a third gen pickup. The booster made a big difference.

 

Found some good info on accident and through of this thread.

" rotors from a 1981-87 FJ60, or a 1981-83 FJ40 will work. there are a few companies making rotors that have the applications wrong in the catalogs, you want to cross this raybestos#9838 or beck arnley#0832028 "