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I had been playing with the idea of converting the Dana 44 from drums to discs when the time came to redo the brakes. Researching showed there were several ways to do it ranging from easy to more difficult. Easiest and most expensive is purchasing an aftermarket disc brake kit. There is the option of using Ford Explorer backing plates and calipers, which will require minimal modifications. The other thing that a number of guys have used is Crown Vic backing plates and calipers, which use the same rotor as the Explorer, but have a trailing and leading caliper setup. And finally the is using backing plates and calipers from a Dana 35. This option appeared to be the most difficult to do and it required heavy modification to make it work. After researching I opted to use the Explorer for my disc conversion as its cheap ~$280 if you use mostly junkyard parts and pretty straight forward. I used the following writeup as my primary resource for information: https://www.naxja.org/forum/showthread.php?t=967146. The first modification needed to use Explorer backing plates is the bolt pattern. The Explorer backing plate has an axle housing bolt pattern that closely resembles the MJ/XJ D44. - 95 - 01' Ford 8.8 rear discs backing plate has a 2" x 3 9/16" bolt pattern - 86 - 90 MJ/XJ D44 has a 2" x 3 11/32" bolt pattern This gives a horizontal difference of 7/32" between the axle housing bolt patterns. The Explorer backing plate needs the holes to be inwardly elongated 7/32" for them to bolt onto the D44 housing. A Dremel with a carbide bit made quick work on elongating the Explorer backing plates. Remove about 1/8" inward side of each hole. I used the D44 retaining plate as a template and to measure when I had removed enough material. When removing the metal with the carbide bit wear gloves. The shaving that are created are super irritating if you get them on the skin, and hang around forever if you don't vacuum them up. Explorer backing plate with holes elongated Here's the D44 retaining plate over the Explorer backing plate after elongating the holes. Finally a test fit of the backing plate on the D44 after elongating the holes. The second problem that needs modification is compensating for the difference in thickness between the Explorer backing plate vs the D44 drum backing plate. - Explorer disc brake backing plates are .350" thick - 86 - 90 MJ/XJ D44 backing plates are .125" thick Giving a thickness difference of .225" between the two. You can have a machine shop custom make a spacer to make up the difference or you can go the easy route and look to Teralex. Teraflex uses a spacer in the aftermarket D44 conversion kit they sell to compensate for this difference. A search on the webpage showed the spacers to be available for purchase by themselves, PN 86261, for $6.99 each. The spacer are .226" thick. The addition of the spacer will require the axle shaft bearings be replaced. When you go to press axle shaft bearing assemblies on the spacer will go between the D44 retaining plate and the oil seal. Make sure the tapered side of the spacer is facing the oil seal. I read conflicting reports of whether or not the stock wheel studs would work. It varied on what material the rims were, steel vs alloy, and the back spacing of the rim. I run the 90's era stock steel D-window rims. Before I pressed the new axle bearing assemblies on I did a test fit the Explorer setup for thread engagement on the lug nuts. Using the old oil seal I put the axle in place with the retaining plate and spacer. The stock wheel studs appeared to be just long enough. I was able to get 5 - 6 full rotations on the lug nuts. That was not enough engagement for my personal comfort so I changed out the wheel studs with some Ford 8.8 disc brake rear wheel studs, Dorman PN 610-368. Axle bearing assembly with Teraflex spacer pressed onto the axle shaft. Parking brake shoes and hardware need to be installed before the axle shafts can be installed. When trying to put the axle shafts in the the Teraflex spacer kept falling down. To keep it centered and in place I put a few dabs of Ultragrey RTV on the spacer to essentially glue it onto the retaining plate. The third problem that needs to be addressed is the rotor hat height. The TJ uses the same rear D44 axle shaft as the M/XJ, and the TJ Rubicon comes with disc brakes on the D44. The TJ Rubicon rotor has a hat height of 2.295" vs the Explorer at 2.275", giving a height difference of .020". Which is negligible, so the use of a an Explorer rotor would/should not be a problem. If using the Explorer rotor the main issue is the center hole. The D44 axle shaft will not fit through the center hole without widening it. About .015" needs to be removed from the inner surface, a flapper wheel could probably take care of that. I read of a few guys have some brake pad drag when using the Explorer Rotor. The other option that a lot of guys use are ZJ rear rotors. The comparison of the three rotors is as follows: Explorer Rear Rotor w/Parking Drum in Hat -Number bolt holes: 5 - Bolt Circle Dimensions: 4.5" -Discard Thickness: .433" -New Surface Thickness: .473" -Outside Diameter: 11.22" -Overall Height: 2.295" TJ Rear Rotor w/Parking Drum in Hat -Number bolt holes: 5 - Bolt Circle Dimensions: 4.5" -Discard Thickness: .433" -New Surface Thickness: .472" -Outside Diameter: 11.22" -Overall Height: 2.275" ZJ Rear Rotor w/Parking Drum in Hat -Number bolt holes: 5 - Bolt Circle Dimensions: 4.5" -Discard Thickness: .374" -New Surface Thickness: .43" -Outside Diameter: 11.22" -Overall Height: 2.33" Again, the difference between the two, Explorer vs ZJ, is practically negligible. I went with the ZJ rear rotors due to the two issues that I read about with the Explorer rotors. Oddly enough I never read of anyone using the TJ Rubicon rotors. However, based off of measurements the change of brake pad drag would still be a possibility. The stock steel brake lines on the D44 will be too long, which will require them to be modified or replaced. I replaced mine as I don't know when the hardliners were last....if ever replaced. The hard lines were run to the rear towards the back of the spring perches. To connect the hard line to the caliper, I used two passenger side lines for an Explorer. I have them running horizontal and inline with the leaf springs to prevent them from getting snagged or caught on anything. While I was doing brake lines the soft line running from the D44 to the bed was clearly the stock length and didn't allow for any flex. A longer brake hose from a Dodge Dakota was put in as well. The last problem to address is the ebrake cables. There are three options that are discussed over and over: Cut the spring off the stock drum cable, fold it over and use cable clamps to secure it to the ebrake arm Purchase the Lokar Clevis Kit and modify them for the drum cable ends Use the Lokar Universal Ebrake Cable Kit and build your own cables I actually went with a fourth option. I thought what about using ebrake cables from a ZJ with disc brakes. I found a pair on a Zj in the junkyard and threw those on. The length is snug but long enough with no modifications needed. I remember reading mixed information on which rims and backspacing will work. I vaguely recall hearing the 90's era 5 spoke and 11 spoke stock rims wouldn't fit. But when researching the stock Explorer rims were the same size and dimensions as Jeep so there is no reason why they shouldn't fit. Further reading led me to believe some people were mixing up Crown Vic brakes. Stock rims most likely will not fit with that setup as the stock rims are 16" rims. But that's just me making conjectures. Anyways, the stock rims had plenty of clearance for the calipers. Several post discussed swapping out the stock single diaphragm brake booster for a dual diaphragm as well as a prop valve for one from a ZJ with disc brakes to provide better braking pressure on the rear discs. I've already swapped in a dual diaphragm booster and I still have the MJ prop valve as my load sensor still functions. Thus far driving around the brakes have worked flawlessly and if the load sensor fails I can install a wildwood adjustable prop vale on the rear line.

1987 Comanche long bed 4.0l Manuel 5 spd, Dana 35 and Dana 30. 3 inch RC lift, 31 bfg ATs Alright, so I've learned a lot about axle swaps but now that I'm looking for a 8.8 out of an explorer, I just want to know what is completely involved. I've looked at some other posts and stuff so I have a rough idea. What do I need get to do this? What do I need to do? Is it simple enough? What cutting and welding and fabricating is involved? Should I get the axle beefed up with a truss while its out? What gears should I do and how much are they? What shafts? Brakes? Ect? Thanks please don't tell me that I shouldn't does this or some other thing about money. I just want to see what's involved and if I want to do this. I have my reasons why and it's also just a learning experience for me, So if you can just answer with a straight forward answers. Thanks

So I've done a good bit of research and can't seem to find what swapping in a ZJ proportioning valve will look like. My plan is to swap to a '96 booster and MC from a ZJ, swap in a ford 8.8 (rear disc), and use the proportioning valve from the ZJ to delete the factory load sensing valve. Any info on the p-valve fitting sizes and line work that would need to be done would be great! Thanks in advance!

I'm in the process of getting rid of the Rustys junk under my 1992 mj short bed 4wd and need some advice for a better ride. Right now the truck is lifted 5ish inches in the rear and 4 to 4.5 in the front with a cheap rustys short arm and spring over kit. I have installed WJ knuckles and brakes. Eaton elocker and 4.11 gears. Went to full crossover highsteer setup with chevy Tie rod ends and WJ brakes. I custom made a new track bar and currently my drag link and track bar are almost parallel and level. I'm in the process of replacing rustys springs with ome springs and a cavfab 3 link in the front. I have bilstien 5100 shocks all around. Here is where it get interesting I have a ford 8.8 disk break rear end I installed and after getting it put in I have realized that I have sagging lead pack on 1 side. The overload leaf has already been removed from the previous owner and it currently is pretty stiff ride in the back. I have contemplated going with oem replacements for $350 rated at 1230lbs. Alcan springs quoted me $630 plus shipping they said they could make a set rated at 1000lbs. Or I'm thinking about ripping it all out and doing a 3 link or 4 link rear with 2 inch lift TJ coils which should fit perfect. It's looking like with the gas tank I don't have room to make a 4 link or crossmember to place the 3rd link on so I'm not sure that having the 3rd link on 1 side might be to much stress for the unibody. I was thinking of making plates that bolts to the frame for the lower control arm mounts and I think that will be fine but the upper control arm mount has me stumped. I have thought about going with an xj or tj or yj fuel tank in the spare tire area but don't know if they would fit. Then I could make a crossmember for the upper and lower links. Has anyone ever seen this done? Do you think it's worth the investment of probably $1000 in materials? Would the ride be any better with say 2.5 lift ome soft springs from rear of a tj then the leafs that are under it now. I will post pictures as soon as I figure out how.

So for about 3 months now Ive had a ford 8.8 ready to swap in including a new 5.5 inch lift. :doh:I have everything to do the lift and swap and i know how to do it, but i haven't yet because its different gearing then my dana 30 upfront right now and i need a drivable car and 4wd here in the upcoming colder months. But now that i have this 1995 4wd cherokee with a non CAD dana 30, I'm going to pull it out and have it re geared and put that in my comanche. I'm not going to build it up yet because i don't have the money because i started school and can't work as much, but i just want to replace what i should and get the parts to re-gear it. I'm just wondering what i need to buy for a re gearing? thanks. Id like to get the parts so that i can do this ford 8.8 swap, new 5.5 alexia lift and then this dana 30 all in one weekend. BTW I'm not doing it myself, but i just want to have all the parts ready to bring to the shop. also, the shop in town here is cool with bringing in your own parts. . :MJ 1: . (me after swap)

So I'm getting all the supplies for my 8.8 swap and i need to get some new 4.10s for my dana 30 cause its geared with 3.08s right now. Whats th best and cheapest ring and pinion and some websites have a lower ratio carrier. whats that? thanks and if i need anything else tell me please.