Rear disc brake conversion help needed on a '99 Ranger

[nofortunatesonII]

I purchased an 8.8 rearend from a salvage yard for my '99 Ranger to replace the 7.5. The rearend I picked up is 3L55 ratio and 28 spline axles. I will be picking up another rearend shortly out of an Explorer which is 3L73 with disc brakes and 31 spline axles. I plan on putting the 3.73's in place of the 3.55 in the Ranger rearend as my truck currently has 3.73 and I really like that ratio. I will either change out the side gears in the 28 spline Traction Lok or else use the entire unit out of the explorer depending on which one is in better shape. I believe the Explorer axles and disc brakes should swap in to the Ranger 8.8 housing. What I am curious about is how much trouble will it be to switch to disc brakes. I would imagine the master cylinder is different, emergency brake cables, but what about the ABS. Do i need to change anything as far as that is concerned. What about the proportioning valve? Thanks. P.S. Use caution when changing the oil filter on a '99 Ranger 3.0L The starter is close by with a HOT wire. Photo below.

 

[dkchrist]

if memory serves me correct the disk brake will not just bolt on and the axle sizes are different (ranger 28 spline vs. explorer 31 spline) the housings are also different. Depending on the year of explorer the abs should plug right in but you will have problems with the proportioning of the brakes. If you have rear abs the master cylinder should be the same other than you will need to add a proportioning valve because drums take lower pressure than discs. As for the e brake i don't know

 

[SkanlaxJMO]

you could just weld some perches up on the explorer 8.8" and put that in..if you can weld.

 

[nofortunatesonII]

I realize that the Ranger is 28 and the Explorer is 31 spline, that is part of the reason I bought 2 rearends to make 1. I know someone who does rearend work and custom builds housings. It would be no problem for him to modify the Explorer housing which would require removal of the sway bar brackets, welding on shock mounts (the Rangers are welded to the housing, the Explorer mounts to plates, not to mention the Ranger has staggered shocks and the Explorer does not), and welding on spring perches. I prefer a factory housing if possible, if not I guess modifying the Explorer rear is the answer. As for the emergency brake, I kept all the cables when I removed the Explorer rear today at the yard. It looks like they should hook to the Ranger emergency brake without any problems. Thanks for the info on the ABS, mine does have the rear ABS on the drum housing. I guess all I need now is the proportioning valve from the Explorer. Thanks to all for replying to my questions.

 

[nofortunatesonII]

The solution...

I took some measurements today and it appears that the Explorer rearend is approx 1/2" wider each side of the center section than the Ranger. The emergency brake cables from the Explorer appear as if they should hook up to the Ranger emergency brake. The flange at the end of the housing where the disc brakes bolt on appear different between the 2 vehicles so no removing the Explorer brakes and bolting them on to the Ranger housing. So I guess the only way to get the disc brakes will to be to modify the Explorer rearend. The added width should not pose any problems. So it appears that in order to put the Explorer rear in the Ranger it is a matter of removing the Explorer sway bar brackets, welding on shock brackets, and welding on spring perches (as well as removing the Explorer perches). The old 7.5 rearend can be used for a donor for these needed parts.