bkahler Posted January 13, 2020 Author Report Share Posted January 13, 2020 (edited) Question: Can a brake MC from a rear drum/front disc vehicle be used on a vehicle with disc front and rear? 1994 Cherokee MC Edited January 13, 2020 by bkahler Quote Link to comment Share on other sites More sharing options...
CO54 Posted January 14, 2020 Report Share Posted January 14, 2020 22 hours ago, bkahler said: Question: Can a brake MC from a rear drum/front disc vehicle be used on a vehicle with disc front and rear? 1994 Cherokee MC Technically yes, that's where the residual pressure valve will help, a proportioning valve wouldn't necessarily be needed in this set up. 1 Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 14, 2020 Author Report Share Posted January 14, 2020 4 hours ago, CO54 said: Technically yes, that's where the residual pressure valve will help, a proportioning valve wouldn't necessarily be needed in this set up. That's good to know. I like the looks of that 94 Cherokee master cylinder. It's not the cheapest around but I still might give it a try. Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 14, 2020 Author Report Share Posted January 14, 2020 In preparation for installation of Charlies front disc kit I removed the front knuckles this afternoon. I was told when I bought the truck that he had just done a brake job and replaced the king pins and bushings. So when I dismantled the truck I never bothered to dismantled the knuckles from the axle figuring I'd leave well enough alone. Well, over the years there were signs of rust showing up in the knuckle/king pin area so I decided since I have Charlies kit I might as well take things apart to take a peek and would make it easier to drill and tap the knuckles. I can safely say that yes the king pins and bushings had been replaced, however they were never greased! I would have eventually greased them before driving the truck but I'm glad I decided to tear into them. At least now I know what I have. So I'll clean them up good after doing the machine work and move on. 1 1 Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 16, 2020 Author Report Share Posted January 16, 2020 (edited) I now have all the bits and pieces on hand for the Rustyhope front disc conversion although I will need to change my spindle nuts. I don't like the style that was on the truck with just three stubs. It's pretty obvious that I'll have to do the reverse castle nut arrangement in order to get things to fit. I am considering having the washers ground down to something less than the current .130" thickness. I'll talk to my local machinist to see what he says. If he doesn't want to surface grind them then maybe I'll have to get my surface grinder set up which I don't really feel like doing! I'm also going to ask about the possibility of drilling a new cotter pin hole out towards the end of the shaft. I think that would be the best approach assuming the shafts can be drilled. Anyone know if the spindle nuts are 3/4-16 or are they 3/4-20 ? My best guess is they are 3/4-16. Thanks! Brad Edited January 16, 2020 by bkahler Quote Link to comment Share on other sites More sharing options...
Dave72dt Posted January 16, 2020 Report Share Posted January 16, 2020 On 1/13/2020 at 10:03 AM, bkahler said: Can a brake MC from a rear drum/front disc vehicle be used on a vehicle with disc front and rear? I wouldn't choose to do that myself. A drum brake setup would have a different residual valve in the system … or at least used to, than a disc/disc. Years ago when masters were actually commonly rebuilt, replacement residual check valves would come with the rebuild kit. You'd pull the old ones out and install new fresh check valves in the master as well as the parts commonly associated with a rebuild kit. Maybe technology has changed or it's been moved to the combo valve. The design of the drum brakes shoe retraction almost dictates a residual to keep them at their most responsive without dragging on the drums. I know it's been done and will say it doesn't matter. I'd check the after market suppliers advertisements and note they differentiate between disc/disc and disc/drum masters. I'd guess there's a reason. On your disc conversion for the front, I'm guessing the hubs are commercially available and not a one-off product. Maybe it would be possible to machine the hub outer bearing race a bit further into the hub, far enough to use that washer at full thickness and the nut with the castle correctly installed. 1 Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 16, 2020 Author Report Share Posted January 16, 2020 12 hours ago, Dave72dt said: I wouldn't choose to do that myself. A drum brake setup would have a different residual valve in the system … or at least used to, than a disc/disc. Years ago when masters were actually commonly rebuilt, replacement residual check valves would come with the rebuild kit. You'd pull the old ones out and install new fresh check valves in the master as well as the parts commonly associated with a rebuild kit. Maybe technology has changed or it's been moved to the combo valve. The design of the drum brakes shoe retraction almost dictates a residual to keep them at their most responsive without dragging on the drums. I know it's been done and will say it doesn't matter. I'd check the after market suppliers advertisements and note they differentiate between disc/disc and disc/drum masters. I'd guess there's a reason. Good information. Until I started doing research on the MC swaps I hadn't realized there was any sort of residual valve in the MC on drum systems. I typically have not rebuilt MCs, instead I usually opted for fresh rebuilt or new units, probably because I tend to be a little on the lazy side From what I've read so far and been told is if using a drum/drum MC a proportional valve needs to be used for the rear lines and a 2 psi residual pressure valve for the front, this is assuming I understood things properly. It's entirely possible I have the details wrong which is something I'm still researching. I'd love to find a cast iron MC that handled disc/disc and fit in place but so far I've had no success. I ordered a MC yesterday that is for a 94 Jeep Wrangler with rear drum/front disc brakes. I found at least one source that sells a rear disc conversion kit for Wrangler drum replacement and they appear to use the same brake MC with no changes. 12 hours ago, Dave72dt said: On your disc conversion for the front, I'm guessing the hubs are commercially available and not a one-off product. Maybe it would be possible to machine the hub outer bearing race a bit further into the hub, far enough to use that washer at full thickness and the nut with the castle correctly installed. The hubs are from a Dodge Diplomat. What you're suggesting might be a possibility. I think the area of concern would be whether or not the outer bearing would be located correctly on the shaft. In other words is the shaft machined as a bearing surface where the bearing would end up. My assumption is it should because it would seem logical that is where the bearing in the original hub would have been located in order to use the cotter pin hole in the axle. Definitely something to look into. Thanks! Brad Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 18, 2020 Author Report Share Posted January 18, 2020 I took the front spindles over to a local machinist to see if he could drill new holes closer to the end of the shafts. 15 minutes later I was walking out of his shop with two new holes in the spindles He wanted $10 and I paid him $20, it was worth the extra because of the time it saved me. In the first picture you can see the extra distance I now have for a larger nut. I plan on cutting slots justs deep enough in the nut for the cotter pin clearance. I also drilled and tapped the the knuckles for the 5/8-18 bolts that are used in Charlies kit. All that's left is to bore out the holes in the two steering arms to 11/16" but first I have to find my 11/16" drill bit! Brad I 2 Quote Link to comment Share on other sites More sharing options...
Dodgeb4ya Posted January 18, 2020 Report Share Posted January 18, 2020 The job done right! 1 Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 18, 2020 Author Report Share Posted January 18, 2020 My Rustyhope intake manifold arrived a couple of days ago. Yesterday I took it to the car wash to wash off the white flux residue and sometime in the next couple of days I'll sandblast it and from there it's paint. I really like the looks of Charlie's conversion and looking forward to installing it Brad . 2 Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 21, 2020 Author Report Share Posted January 21, 2020 The Cherokee axle I bought on ebay arrived today. I wasn't sure if it was going to include the calipers and rotors and as it turns out it did not. It definitely has some rust on the outer extremities but as near as I can tell, nothing serious. The worst of the corrosion is probably on the caliper mounting brackets so I'll have to look closely at those, hopefully I won't have to replace them. Spring perches, rotors, calipers, hoses and brake pads are now on order and I should have them by the end of the week. Long before I'll need them I find it interesting that it has a mixture of mostly metric and an sae thread or two. The bolt that holds the flex hose from the frame to the axle is the same size as the one on my original axle. Even better is that means I'll be able to use it for my original axle brake hose and Y fitting along with it's associated breather tube. This coming weekend I'll get the torch out and cut off all of the misc mounting brackets and prep the tube for the new perches. I did verify the distance between wheel mounting surfaces (wms) and it's 60.25". My original axle is 62.25" so I'm planning to add 1" spacers to each side to bring the wms back to factory specs. Not sure if I'll use an adapter that bolts to the hub and has it's own studs or buy and install longer studs and just use a spacer. I think I prefer the latter. One thing I'm confused about is exactly which Spicer axle is this? I was under the impression that it was a Spicer 35 but as near as I can tell the rear cover seems to imply that it is a Spicer 44 which doesn't jive with anything that I've read. Brad Quote Link to comment Share on other sites More sharing options...
Young Ed Posted January 21, 2020 Report Share Posted January 21, 2020 are you planning on using stock wheels? otherwise you could just get 1 inch wider wheels and forget the spacers all together Quote Link to comment Share on other sites More sharing options...
CO54 Posted January 21, 2020 Report Share Posted January 21, 2020 (edited) You got yourself a Dana (Spicer) 44. Solid axle with a great supply of replacement and upgrade parts options. If you doing anything with internals, verify the spline count, there was a change in the count in the mid to late 90's. Are you going to use the parking brake on the trans or the rear axle? Edited January 21, 2020 by CO54 3 Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 21, 2020 Author Report Share Posted January 21, 2020 2 hours ago, Young Ed said: are you planning on using stock wheels? otherwise you could just get 1 inch wider wheels and forget the spacers all together Stock 16" wheels with stock hub caps. I like the look.... 1 Quote Link to comment Share on other sites More sharing options...
Young Ed Posted January 21, 2020 Report Share Posted January 21, 2020 1 minute ago, bkahler said: Stock 16" wheels with stock hub caps. I like the look.... can't blame you there. I have stock wheels on most of my cars. 1 Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 21, 2020 Author Report Share Posted January 21, 2020 55 minutes ago, CO54 said: You got yourself a Dana (Spicer) 44. Solid axle with a great supply of replacement and upgrade parts options. If you doing anything with internals, verify the spline count, there was a change in the count in the mid to late 90's. Are you going to use the parking brake on the trans or the rear axle? Last night I found Randy's Worldwide site that shows a listing for for what looks like my axle and it's listed as a 99-04 Dana 44HD Grand Cherokee. This diff came out of a 97 Grand Cherokee and has the narrow WMS compared to the 99-04 which is something like 5" wider. I think what the real story is Jeep used a Dana 44 in the rear and a Dana 35 for the front axle on the Grand Cherokee's. I plan on using the original transmission mounted parking brake. I went to a lot of effort finding all the rights and getting the band relined so I'm sticking with it I will be pulling the axles so I can replace the axle seals so I'll check spline count at that time. Thanks! Brad 1 Quote Link to comment Share on other sites More sharing options...
CO54 Posted January 21, 2020 Report Share Posted January 21, 2020 (edited) Jeep used the Dana 44 front and rear on, 93-98 Cherokee, Grand Cherokee, and Wranglers, however during the same time they also used a Dana 35 rear with a Dana 30 front. These where all on a 5 x 4.5 bolt pattern. GC from 99-04 flipped to the Aluminum Dana 44 with 5 x 5 bolt pattern. Wranglers stayed on 5 x 4.5 until 2007, when they flipped to 5 x 5. Jeep stopped using Dana 35's with the end of 2006 Edited January 21, 2020 by CO54 Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 22, 2020 Author Report Share Posted January 22, 2020 4 hours ago, CO54 said: Jeep used the Dana 44 front and rear on, 93-98 Cherokee, Grand Cherokee, and Wranglers, however during the same time they also used a Dana 35 rear with a Dana 30 front. These where all on a 5 x 4.5 bolt pattern. GC from 99-04 flipped to the Aluminum Dana 44 with 5 x 5 bolt pattern. Wranglers stayed on 5 x 4.5 until 2007, when they flipped to 5 x 5. Jeep stopped using Dana 35's with the end of 2006 The diff I have has the aluminum center section with steel tubes but it does have the 5x4.5 bolt pattern. Quote Link to comment Share on other sites More sharing options...
CO54 Posted January 22, 2020 Report Share Posted January 22, 2020 97 GC Diff would have the 5x4.5, some where aluminum centers. 1 Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 27, 2020 Author Report Share Posted January 27, 2020 Spent several hours on Saturday and Sunday cutting off all of the extra brackets on the Cherokee axle. I had planned on using my acetylene torch to cut the brackets off and then smooth them out with the grinder but after cutting about 2" into a bracket my acetylene hose cracked and I had a nice little fire right at the torch handle! That meant I had to use cutoff wheels to remove everything. So in spite of the equipment failure I manged to make the axle tubes look pretty decent, it just took longer than planned. Sorry no pictures, I was bundled up in heavy clothes and gloves and didn't take the time to take any. The Cherokee axle obviously came from a northern state as evidenced by all the rust. I now have all of the rust cleaned up with the exception of the two backing plates and the caliper brackets. Those pieces are currently soaking in Evapo-rust. I'm pretty sure the caliper brackets are salvageable and probably the left backing plate but the right plate has some rust through that might be more than I want to deal with. Unfortunately the only way I can buy the backing plates is as a complete set which includes the caliper brackets and parking brake shoes at about $250 for both sides. That's a lot of money when I only need the two stamped sheet metal backing plates. After the discussion on leaf springs a few days ago I decided to go with liner inserts sold by Speedway Motors. I've already received the shipment so the next step is to start dismantling the leaf springs so I can remove the paint between the leaf springs. I'm thinking I'll try using a wire wheel first to see how well that works. I really hope to have all of the spring work, axle modifications and front disc brakes installed before the end of March. Well, I can dream anyway.......! Brad 1 Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted January 27, 2020 Report Share Posted January 27, 2020 be sure the rear sliding caliper brackets are not showing evidence of hammering and the caliper will be able to slide nice and smoothly...these are pretty heavy items but I have seen them damaged. So particular models will not service a caliper without this attaching bracket due to this chatter/hammering damage. Quote Link to comment Share on other sites More sharing options...
Young Ed Posted January 27, 2020 Report Share Posted January 27, 2020 31 minutes ago, bkahler said: The Cherokee axle obviously came from a northern state as evidenced by all the rust. I now have all of the rust cleaned up with the exception of the two backing plates and the caliper brackets. Those pieces are currently soaking in Evapo-rust. I'm pretty sure the caliper brackets are salvageable and probably the left backing plate but the right plate has some rust through that might be more than I want to deal with. Unfortunately the only way I can buy the backing plates is as a complete set which includes the caliper brackets and parking brake shoes at about $250 for both sides. That's a lot of money when I only need the two stamped sheet metal backing plates. That's a fairly new part-did you try your local mopar dealership? Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 27, 2020 Author Report Share Posted January 27, 2020 13 minutes ago, Plymouthy Adams said: be sure the rear sliding caliper brackets are not showing evidence of hammering and the caliper will be able to slide nice and smoothly...these are pretty heavy items but I have seen them damaged. So particular models will not service a caliper without this attaching bracket due to this chatter/hammering damage. That or something similar is my one concern. Of the two pads the pad that the piston presses on is designed to move inward towards the rotor. The caliper itself also slides in and out on two bolts or studs to compensate for pad wear. Currently there is an obvious wear area in the caliper bracket that corresponds to where the sliding pad is located. What I don't know is how much if any this will impact brake operation. So far I've not found any pertinent information searching online. The only thing I can take way from that fact is maybe it's not a problem. This is something I need to stew on a little more I guess. Brad Quote Link to comment Share on other sites More sharing options...
bkahler Posted January 27, 2020 Author Report Share Posted January 27, 2020 12 minutes ago, Young Ed said: That's a fairly new part-did you try your local mopar dealership? I've checked a lot of the online mopar parts sites and all show as discontinued. One of them does list the right side as being in stock but their website hangs during the last step when ordering and worse, they provide NO contact information anywhere on their website! I hadn't thought about checking locally but there is a Jeep dealer not far from me so maybe that will be my next attempt. Thanks! Brad Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted January 27, 2020 Report Share Posted January 27, 2020 pin mounted studs for the calipers are often failure free given the plating on the slide pin has not disintegrated and turned to rust...these pin units are less trouble on the average as they are equipped with sealing boots. 2 Quote Link to comment Share on other sites More sharing options...
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