GT4 G80 axle JD7 brake swap

[A93obs]

Pretty sure. I've had a JD7 sf that was 2 1/2". My current JD7 ff is 3 1/2", same as my JB8 ff.

I only put that out there because when ordering drums/shoes for a JD7, it will give both width options without identifying the qualifier. Full float 7's have 3 1/2", semi float has 2 1/2".

That’s good inside info that could cause a problem if not known .. thanks

 

[A93obs]

I plan to keep my vacuum boost and run jb7 or jb8 c2500 calipers up front ..will that FF having 3.5” shoes setup make any change or affect the vaccum boost from doing its thing properly on an 1” larger shoe size

Prob not hydro swapping just don’t wanna get into all that currently

 

[Supercharged111]

7 should be 2.5" shoes with press on drums and 8 from an SUV/SRW is gonna have the slip on drums and 3.5" shoes. So easiest way to tell (if not dually) by looking at a 14BFF is whether or not those drums are slip on.

The only time you have to grind brake pads that I'm aware of is when using 2500 pads on a 1500 rotor (4wd, can't speak to 2wd). If you're swapping the whole entire unit over it's gonna be bolt in and go. I'd swap in the diff, booster, and MC as well so it all matches. I switched from a NBS master over to JB7 (or JD7? the HB one) when I did hydroboost in my 1500 and that was the day the brakes finally felt proper. Of course it already had the larger front calipers and JB6 out back.

 

[A93obs]

should be 2.5" shoes with press on drums and 8 from an SUV/SRW is gonna have the slip on drums and 3.5" shoes.

This is all mix match conversion stuff .. the Donor truck I am taking the 2500 spindles from is a JD7 truck that much I know .

I do not want to deal with swapping to hydro atm.. even tho it’s recommended..so my main pick for the truck was to get the 14ff and swap it into my 93 1500 and do away with the 10bolt .

While at it .. if the calipers were good I was gonna use them and the spindles off this c2500 JD7 donor truck and purchase clean new UCA and rotors.
I just want to stay vaccum boost but run the better jb7-8 calipers on 8 lug rotors and run the 14ff how it is of course with new shoes and hardware.
So over all the main grab was for the 14ff and the front spindles so I can 8 lug swap properly.
I just need to know if I swap the spindle and new 8 lug rotors can I alternatively run a jb7-8 caliper swap that utilizes vacuum boost as its Oe component. Another words 13” drum 3.5” shoes and jb7-8 calipers in front is that gonna be doable

 

[Supercharged111]

Totally doable. I just can't wrap my head around you avoiding hydroboost when all the stuff for it is on the donor truck along with the proper master cylinder.

 

[Schurkey]

Leading a horse to water...