Hey everyone, i have a 94 f150 with l6 motor and a auto 4 speed tranny. Ive never really been much into the look of brake drums so i want to try to convert hte rear into brake discs. THe simplest way of doing this is for me to go to a local junkyard and i can get a rear axle for about 20 bucks if i pull it myself. I am aware that the earliest truck ot have four wheel brake discs is around hte 2000 f150. i have seen the piece and i feel it wont be much of a difference, but i was wondering if the differential might be significantly different between the 94 f150 and say a 2000 f150. Im hoping someone out there might have a bit more experience with axles than me cause im drawing a blank. Thnaks for any help anyone can provide.

 

The wheel bolt pattern was changed in 97 when the new F150 was introduced (first year for disc rear brakes too). I think the axle itself would swap (I don't know that for sure), but you would have to use rear wheels from a 97-03 F150.

 

i understand what you mean but ive seen all kinds of wheel swaps amongsts all f150 truck models. Ive seen a 95 f150 before with the 16 inch wheels that come on the 2000 f150. I know the bolt pattern slightly change but i dont think it is enough to need to change the wheels. my cousin has a 2000 f150 so i think ill have him come over one day and we will trade wheels to make sure of these but i dont thnik itl be a problem. And my uncle has a 1998 f150 and it has break drums on the back, the earliest one i know of to have discs is 2000. THnaks for your help though if the axle will swap easily then its a go for the project but i have to double check on the wheels.

 

oh by the way anyone have any idea on any differential differences between the two models. THe axle seems similar but i need to know if the differential is the same.

 

Pearl,

You will want to check the following on your existing rear:
The gear ratio in your existing rear axle
Distance between each wheels mounting surface (hub flange or the face of the drums)
The distance from the axle tube center line (horizontal) to the u-joint saddles on the pinion yoke
The distance between the differential center line (verticle) to the center line of each spring perch

Once you have all those measurements you can determine of an axle from one of the later trucks will bolt in.

Regarding wheel bolt circle. In order to use your existing wheels on a new axle the bolt circle must be the same. Not mearly close, the same. You may be able to get the wheels on but the tappered seat of the lug nuts won't be able to seat into the holes in the wheels. Very un-safe.

Dan

 

You might want to go this route.
http://broncograveyard.com/bronco/i-...rake_conv_.htm

 

Discs were offered starting in 97--they were an option, so not all F150s had disc rears, but 97 was the first year for them regardless. I agree with Dan, your wheels and axle bolt patterns need to match exactly.

 

Yes, your wheels need to be identical. Close is not good enough for safety reasons.

Also, you will have to use an adjustable proportioning valve and possibly a new master cylinder. Disc brakes require very different pressures than drum brakes.

 

First off thanks to all of you who put in your 2 cents, especially thanks to alz for the link. I think i will use that kit since its true about the bolt patterns, i want safety first since i got like 4 kids in the truck most of the time. I guess i thought it be much easier to get through with the project but i didnt think of all the details involved. I didnt understand much about the kit though apparently it doesnt come with calipers?!?! but either way it seems to be the best choice so thats the first thing on my list for this summer. Im gonna be hte only truck in dallas thats 94 with four wheel brake discs....sweeett!!!! THanks again to all of you guys for the help!!!!!!!!!

 

An idea that a lot of people overlook is having the axle flanges and brake rotors redrilled for a different wheel bolt pattern. Any reputable machine shop can handle this job no problem. The downside is that this would obviously add to the cost of the whole axle conversion, so by the time you find your axle of choice and have it reworked, you could well be money ahead if you just ordered the kit from the Graveyard. Or you could be money behind...pretty close call either way until you talk to a machine shop.

Pat

 

Pat, I just had that thought too as I was catching up on this thread. Could the brake rotor setup from the later model trucks be used on the earlier 8.8" rear using the stock axles? All that would require (assuming everything else matches and bolts-on, which I have no idea if it will or not), would be to re-drill the rotors for the correct bolt pattern so they slip on the older axles. Definitely something to look into.

 

Eric...yeah, I've had that exact same brainstorm going on since '01 when I found out the '97 and newer trucks had discs as an option. I think in this case the only critical measurement would be the distance between the axle flange and the brake mounting pad on the axle housing; that would ensure that the caliper would line up with the rotor.

Of course, it goes without saying that this idea might only apply to the 8.8" rear...I don't have a clue whether or not those 9¾" rear ends use the same brake hardware.

The more I think about this idea, the more I might actually try it someday! I've been putting a leaky rear axle seal off all winter...when I get around to changing it, I'll try to remember to do some measuring.

Pat

 

Let us know what you find out. I wouldn't mind swapping to rear discs somewhere down the road, so to speak.

 

wow its kinda cool how many people are interested in this (yes! i started a long thread). But with the idea of redrilling rotors comes the long delay of trial and error. I need my truck every day so i need not only something that will do the job but also a kit that wont take long to install. i saw the website for the kit and it seems like the best way to go except the kit doesnt seem to come with all the things it needs. It has extra prices all over the place, like for calipers and other stuff, this might actually be kinda pricy but the last thing i did to it were the full crystal clear headlights so i need a big change to keep my love for my truck alive. THanks to everyone here ur help is appreciated!