Plymouthy Adams Posted January 9, 2015 Report Share Posted January 9, 2015 your early unit will be tapered axles..and from my inter-sub book you should not have a 10 spline axle for that 741 case......in the truck line up with a C style axle you can have 30 and 16 splines and in the car line up all I see are C style axles and 30 splines....but also for the truck you could have a G series axle (with domed hub) and those are 16 spline axles...you may have to go a bit deeper in identifying the actual donor you have for your vehicle.. Quote Link to comment Share on other sites More sharing options...
48Dodger Posted January 9, 2015 Report Share Posted January 9, 2015 The feds in 67 mandated dual reservoir for safety reasons. M/Cs that are below the calipers need 2 lbs residual to prevent flow back. Disc brakes basically do not use residual pressure like the drums because the brakes would drag. Rears drums need a 10 lb residual valve and a port valve for tuning if doing a upgrade/mod etc. Drums use the rediual to overcome the spring pressure on the pedal. That spongy feeling you can get with a poorly tuned drum/drum system. The rear brakes should act as a rudder to assist the front brakes in stopping....not "come in" first. Side Note: When I race the 72 Charger in circle track, the rear brakes are almost non existent. It allows the back end to "drive" itself (read that as drift or slide) around the corner. It scubs speed, but is helpful with a bigger car like the Charger. I will not build or drive a Camaro...lol. 48D 2 Quote Link to comment Share on other sites More sharing options...
Jeff Balazs Posted January 9, 2015 Report Share Posted January 9, 2015 Good point Tim. I had residual valves in my initial install (per several guidelines) and had to remove them to get my system working properly. Also I fitted a dual reservoir M/C that was as close a match to the actual brake components I used. Since I had swapped in an axle from a Grand Cherokee with rear discs I used the M/C from that same model. Balance was close but the rears were locking up first until I spent some time adjusting the PV. Modifying a brake system is serious business. It is not something to be taken lightly or scrimp on. Failure is not something any of us want to hear about. Jeff 1 Quote Link to comment Share on other sites More sharing options...
NiftyFifty Posted January 9, 2015 Report Share Posted January 9, 2015 I got lucky, the MC and prop valve I took from a Cherokee worked what I would call perfectly with the front disc setup and YJ rear diff. There is a thread with pictures out there somewhere if others are interested. Quote Link to comment Share on other sites More sharing options...
HanksB3B Posted January 9, 2015 Report Share Posted January 9, 2015 I got lucky, the MC and prop valve I took from a Cherokee worked what I would call perfectly with the front disc setup and YJ rear diff. There is a thread with pictures out there somewhere if others are interested. I'm interested and thanks in advance for providing a link ! and Look what you started by starting this topic Edroesuave, Personally I appreciate all the input from everyone that knows about Mopar and general automotive technology. I'm sure I'll be influenced one way or another. Thanks, Hank Quote Link to comment Share on other sites More sharing options...
NiftyFifty Posted January 10, 2015 Report Share Posted January 10, 2015 http://p15-d24.com/topic/19866-master-cyl-swap-from-90-cherokee/?hl=%2Bcherokee+%2Bmaster+%2Bcylinder#entry299772 Here is my swap, still working great...well last time I drove the truck in the spring Quote Link to comment Share on other sites More sharing options...
HanksB3B Posted January 11, 2015 Report Share Posted January 11, 2015 (edited) Thanks 4mula-dlx, Looks like Paul and you went at the master cylinder swap at the same time. It's nice to have an online partner, one of the best things about our forum. Hank Edited January 11, 2015 by HanksB3B Quote Link to comment Share on other sites More sharing options...
NiftyFifty Posted January 11, 2015 Report Share Posted January 11, 2015 I think I was first and he was right behind me and maybe made a few steps easier.... Either way IMO it's a very easy swap for a big gain, and lots of them out in the wrecking yards and fairly cheap remans online. Today I'm still struggling with my power steering swap, built the new column bracket tonight, and managed to scratch my new column up.... Just one of those nights. Quote Link to comment Share on other sites More sharing options...
John-T-53 Posted January 12, 2015 Report Share Posted January 12, 2015 I'm still running a stock, single chamber, master cylinder on my truck with Rusty Hope disc brake conversion up front. I didn't add any residual valves and it all works quite fine for me. Some may argue that I'm tempting fate, but it works for me. Merle How's the pressure you have to apply with your foot compared to the original all-drum setup? The only reason I'm not switching to front discs is because I think I'll make the physical work too hard, as discs don't "assist" the pedal like drums do But, per your post, all seems to be ok? I remember PP also seemed to be happy with his discs, and watching him tearing through Tim's driveway a couple years ago after you fixed his wires; he seemed to stop ok (like we'd hoped at the time, lol). 1 Quote Link to comment Share on other sites More sharing options...
John-T-53 Posted January 12, 2015 Report Share Posted January 12, 2015 I have posted this many times but not in this thread. Just another source for a differential swap. Don, what's the source on this? I'd like to see if I can fill in the blanks with C-body rear ends as well (C-bodies always seem to get left out). Quote Link to comment Share on other sites More sharing options...
John-T-53 Posted January 12, 2015 Report Share Posted January 12, 2015 I did some research and found out I have a Mopar 8 3/4" rearend.Cast into the driver side of the case is the number 1820657 (1957-1964) identify the smaller 1 3/8th-inch-diameter, 10-spline pinion shaft, and are often called the "741" case.Now to find a replacement axle. My first classic truck was a 53 GMC, I worked on it alot and didn't hardly drive it. This truck I want to drive it more than I work on it. 8 3/4" is a good one to have - you should be able to get new ring and pinion gears, if needed, and have any ratio you want. Plus it'll be all Mopar. 8 3/4" pumpkins have the top two studs close together - closer up pics? Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted January 12, 2015 Report Share Posted January 12, 2015 Don, what's the source on this? I'd like to see if I can fill in the blanks with C-body rear ends as well (C-bodies always seem to get left out). A forum member sent me that chart about 14 years ago. I do not know where he got it. Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted January 12, 2015 Report Share Posted January 12, 2015 How's the pressure you have to apply with your foot compared to the original all-drum setup? The only reason I'm not switching to front discs is because I think I'll make the physical work too hard, as discs don't "assist" the pedal like drums do But, per your post, all seems to be ok? I remember PP also seemed to be happy with his discs, and watching him tearing through Tim's driveway a couple years ago after you fixed his wires; he seemed to stop ok (like we'd hoped at the time, lol). The smaller diameter master cylinder you use the less foot pressure is required. I used an ECI dual master conversion on my car and there system has a mechanical advantage feature that requires less foot pressure. Quote Link to comment Share on other sites More sharing options...
NiftyFifty Posted January 12, 2015 Report Share Posted January 12, 2015 My pedal pressure is great, I wish my 67 monaco had as great and firm a pedal as the truck Quote Link to comment Share on other sites More sharing options...
John-T-53 Posted January 12, 2015 Report Share Posted January 12, 2015 No doubt the T5 is a great way to go. I especially liked the way JohnT53 accomplished the installation. I forget where the T5 comes out of and how hard are they to find and for how much.they cost. Don you are not thinkink about going back to your old rum running days with your car now are you ? I see alot of those moonshiners on TV live down your way. Hank Thanks Hank. I wanted to post a link here but now I can't find that content anymore. It was under the "old" forum, around 2011. I can't seem to search by "topics started by (me)". So maybe it is lost? :-( Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted January 12, 2015 Report Share Posted January 12, 2015 just a simple entry into a search engine...here is one..there are other sources... http://www.bigblockmopar.nl/tech/mopar-rearaxle-dimensions/ Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted January 12, 2015 Report Share Posted January 12, 2015 How's the pressure you have to apply with your foot compared to the original all-drum setup? The only reason I'm not switching to front discs is because I think I'll make the physical work too hard, as discs don't "assist" the pedal like drums do But, per your post, all seems to be ok? I remember PP also seemed to be happy with his discs, and watching him tearing through Tim's driveway a couple years ago after you fixed his wires; he seemed to stop ok (like we'd hoped at the time, lol). I don't know if the pedal pressure is any more or less than the all drum setup. All I know it that it stops a whole lot better with the discs up front. Maybe my drums weren't set perfect. It did stop fairly well, but I would also notice a little fade under heavy use. Now I have great confidence in the brakes at any speed. Merle Quote Link to comment Share on other sites More sharing options...
HanksB3B Posted January 13, 2015 Report Share Posted January 13, 2015 (edited) Thanks Hank. I wanted to post a link here but now I can't find that content anymore. It was under the "old" forum, around 2011. I can't seem to search by "topics started by (me)". So maybe it is lost? :-( John's official T-5 thread: http://p15-d24.com/index.php?showtopic=23955 I maintain a Microsoft Word file called "Pilothouse Threads" in which I copy/paste the address of threads of special interest or excellence. I have to hand it to the moderators when they switched servers and graciously provided a solution that allowed me to re-path the hyperlinks (as above). Now if only I can find the path to Tim's Starter Lever removal. I have to do the install part...but it's a ways down the road as I need to get busy on restoring FEF's Radio first. Mark has magnanimously given me till spring because about now I imagine Mark can't even find the garage FEF is parked in. I guess it's just the way it goes in Minnesnowta. In an attempt to steer this thread back on topic: Davin: "I used a MOPAR specific home-made axle puller which my old mate Arnold made for me".. So I guess I get to see my "old friend" Scott here stateside and he'll help me create a similar tool. I think I can explain how I think it works, but I'm not totally sure. 1.) the threaded rods act as legs and maintain the distance between the end of the axle housing and the puller plate on the tool. 2.) The central nut on the tool that is inline and attached to the axle itself is turned clockwise which pulls the axle out. Advice from mechanical geniuses greatly appreciated, Hank Edited January 13, 2015 by HanksB3B Quote Link to comment Share on other sites More sharing options...
John-T-53 Posted January 13, 2015 Report Share Posted January 13, 2015 THANK YOU SIR! That reminds me... I need to add a few things to the topic to bring it up to date. Things have come up during the last couple years that need to be shared. Quote Link to comment Share on other sites More sharing options...
Jeff Balazs Posted January 13, 2015 Report Share Posted January 13, 2015 John; You should expect it to feel much like disc brake equipped vehicle of the late 60's or 70's that doesn't have power assist. Those of us of a certain age are quite familiar with that "feel". No big deal though it is something you get used to fairly easy. I would think this mod would go quite well with the other stuff you have already done. Going to discs is by far the best mod I have made. Jeff Quote Link to comment Share on other sites More sharing options...
Desotodav Posted January 13, 2015 Report Share Posted January 13, 2015 That's exactly how my home-made works Hank, but Ed's method would work just fine also. I had a tool made as I have a few trucks to restore. I'll get back onto converting my second 3.54 diff for use in the 52 truck when I return home next week. Quote Link to comment Share on other sites More sharing options...
pflaming Posted January 13, 2015 Report Share Posted January 13, 2015 I do not need a lot of foot pressure with my disc brakes. I drove the Phoenix to the Sequoia National Park last March on a pull / heat test going up and a brake test coming down. The elevation change is six thousand feet in some 3O miles. The temp did not change, with a 3:73 rear axle it never lugged down and it pulled the hill to the top in 3rd gear. On the way down I never had any brake fade, they held nice and even all the way home. I'm very pleased. I do wish I had put in a 3:54 for freeway driving. I can easily stay with the truckers and pass at will, but a 3:54 would give me lower RPMs and less engine noise. Quote Link to comment Share on other sites More sharing options...
HanksB3B Posted January 13, 2015 Report Share Posted January 13, 2015 Paul, that sounds like an inspirational drive, may you find the time to finish over this winter and take that ride over to Tims this spring. Davin, I guess from the standpoint of cost, amount of use and ease of fabrication Ed's tool and method should be the first attempt. (Rod that insinkerator drain insert may do it in principal when combined with Ed' method) Thanks guys and Davin enjoy your time with your Mum, Hank Quote Link to comment Share on other sites More sharing options...
Edrowesuave Posted January 14, 2015 Author Report Share Posted January 14, 2015 I'm trying to pull the axle shaft out and it doesn't want to come out.I'll try using Young Ed's PVC spacer method tomorrow.I really like HanksB3B's axle puller.I think I have some pvc laying around here somewhere. After I get the axle out I hope to find a replacement. I think it's pretty neat how you can swap out the gear assembly on these 8.75 mopar rearends Quote Link to comment Share on other sites More sharing options...
Young Ed Posted January 14, 2015 Report Share Posted January 14, 2015 Try it you'll like it. They aren't in there that hard. Quote Link to comment Share on other sites More sharing options...
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