baddog8it

My next major project was to be a rear disc conversion on 'The Beast'. The reasoning was that I knew that one rear brake was screwed up, and to do any work on the rear brakes requires pulling the axle. My thinking was that the conversion (which from sales literature sounds really easy) would save me from ever having to pull an axle after that if I only had to install new brake pads. I was looking at the ruffstuff kit for my Dana 70U rear. After reading your right up, I'm rethinking this project. Maybe I'm better off just keeping (and fixing) the factory brake setup. One question - I didn't understand where the water in the differential came from. Was the axle left out in the rain with the axles pulled?

Thanks for the input. I was leaning towards new calipers. I'm just hoping that this project doesn't keep growing to the point where I'm replacing all the brake lines.

I knew I had a brake problem - the rear drivers side brake was sticking. Don't drive the beast but once a week, so was biding my time until I did a rear disc conversion. Lately though, I noticed that the brakes (all of them) seem to be holding more. About a week ago, just by chance, I happened to be looking in the general direction of the floor when I turned off the ignition. I noticed that the brake pedal moved. I restarted the engine and noticed that the brake pedal went down by itself. That explained my problem. With the high vacuum of idle, the brakes were holding the truck, but when driving (less vacuum), there didn't seem to be much problem. Time for a new brake booster. I was also going to replace the master cylinder because the lid seal was crap. On to the real question... Sunday morning I put on a new master cylinder and brake booster. Piece of cake. Was going real smooth. Too smooth. Got set up to do the bleed. Crawled under the first corner, put the wrench on the bleeder screw, cranked too hard - bam! Broken bleeder screw. Started to drill it out when the rain came. Project on hold while I evaluate my situation. Two questions: 1. What size is the bleeder screw? Various resources show different dimensions. 2. Should I just replace the whole caliper? The front brake pads and discs seem to be in good shape. I would assume the calipers are the original (now almost 35 years old). New calipers aren't that expensive. I can go to a lot of work getting the old bleeder screw out, and still have the possibility of screwing up the seating surface or the threads. Just looking for a bit of feedback..

Mystery partially solved. I've confirmed that I have the Dana 70 rear end. I gathered that by the tag info as well as the axle tube diameter. The diameter for the 70 is published as 3-1/2" (mine measured 3-9/16 - lots of rust?). The diameter for a D60 is 3-1/8". The diameter for a 70HD is 4". I'm seriously debating putting disc brakes on the rear end. Seems pretty easy and not expensive. Upside is that they brake better, are more reliable and if only replacing pads - can be maintained without pulling the axle. The kits are readily available, or you can piece it together yourself and just buy the mounting bracket. Downside is that if I want a mechanical parking brake, it adds $150+ to the cost (the calipers come from mid 70s era Cadillac Eldorado. There is still one mystery on my mind. The differential casting should have a model number on it, which I would assume to be "70", but it appears to be "NC". Any thoughts? I also realized that there appears to be another metal tag at the very top of the differential. I'll have to wait until the next time I drop the spare tire to check that one out. Per the Dana manual, it is saying that the rear end on my truck only got put on chassis models. I really need to get my hands on the build sheet.

All good advice. I'll do some research on the nut size. Will also be checking local auto parts return policies. Snow is on the ground and can't fit the beast in the garage - might be awhile before I really dig into it. Thanks all for the help .Will post after I've made some progress .

Now this is starting to make sense... I believe that the truck has always been a full/complete vehicle (not 100% sure, but would be willing to bet money on it). No, have not tried removing the rear drums yet. If it matters any, although it is a 1985 model, it was actually produced on 3 Oct 1984.

I don't have a certification label. Now that it's mentioned, I need to contact Ford and see if they can get me one. I did get a build date from them, but didn't know at the time to ask for a build sheet. I'll have to wait until I can access my pictures at home to give you any more info on the differential/axle tag. Going off of the 3.54 ratio, I figure it's one of the following: Ford B3 Dana 5.3M Limited Slip Ford 33 Dana 6.25M Ford G3 Dana 6.3M Ford 73 Dana 6.3M Ford 43 Dana 7.4M Ford D3 Dana 7.4M Limited Slip Ford F3 Dana 8.2M Locking Ford 63 Dana 8.2M

I'm planning on doing a full brake job and am making the assumption that my beast can use new drums and rotors. This work is being accelerated due to the fact that it feels like my brakes are staying partially engaged after I remove my foot from the brake pedal. I've also noticed a drop in my mpg, although this could be more due to the cold weather (both kicked in about the same time). After drives, I've checked the wheel temps and feel nothing out of the ordinary. It appears that MAYBE the brakes are letting loose once I start moving again. I'm trying to save myself the trouble of tearing everything down, surveying to determine which parts are needed, and then reassembling, only to take it back apart later after the parts arrive. (this is my daily driver) When shopping for rear drums, many of the parts on my favorite parts web site mentions 10.25 ring gear. I have no idea what my ring gear size is. What info I have gleaned off of my differential is that it has a 3.54 ratio. Looking at other info on this (fantastic) website tells me that my rear end could be one of eight different models. I started researching each of these 8 models, but I was getting nowhere fast - not finding anything telling me the size of a ring gear. Here's the digits that I've gotten off of my differential: 3 54 VE17A YA 60 247 1 I do plan on adding a camper in the near future (undecided on a truck slide-out or a pull behind - what appears in the local used market will dictate), so I'm leaning towards heavy duty components (vs economy or daily driver). Any sage advice?

Quick question - I don't have a build sheet available, so what's the simplest way to determine if my beast has the factory trailer wiring? Edit - a bit of clarification. Looking at the '85 EVTM on page 134, it appears that the 'TRAILER OPTION' includes a 'TRAILER ELECTRIC BRAKE CONTROL' which is attached to the brake pedal. Compare that to the diagram on page 79 (showing turn/brake lights), there are greyed out areas labelled 'TRAILER ONLY'. Are these areas and items labelled 'TRAILER ONLY' the same as the 'TRAILER OPTION'? i.e.. If I don't have the trailer option, I can and should ignore anything labelled 'TRAILER ONLY'?

So last night I dug back into it. First I double checked my wiring at the C305 connector - all was fine. Then pulled the steering wheel. Low and behold, this is what I found... I cleaned up everything, used some liquid tape to insulate the exposed copper, and tucked it away out of harms way. I was confident that that a bare wire rubbing on the steering wheel had to be the problem and set about putting everything back in place - fully wrapping it up. Reinstalled brake switch connector, hazard flasher and verified I had a good fuse in place. UGH!! Symptoms still exist (at least some of them). I unplugged the brake switch connector so that I'm not running down the battery. Everything still seems to act the same with the possible exception of the fuse shorting. I think that either the flasher/turn signal assembly is wired wrong or has an internal short, or there is a problem in an aft wiring harness as others have alluded to. I'll have to wait for the driveway to dry off enough so that I can go crawling around under the rear end of the beast! thanks for the support and helpful info! Hopefully I can get this resolved quickly.

when brake switch disconnected, there are no brake lights (but running lights work normally)

Nope, no brake used (shouldn't have mattered anyway - brake switch was disconnected). Yes, when brake switch connected and hazard flasher removed - brake lights on (dim).

So, while parked, no lights on, nothing amiss. Started my drive to the auto parts store, and I here the snap of the fuse after about 2 minutes of driving. This tells me that there is a leak/short thru the hazard flasher or in the wiring between the fuse the brake switch. I then pulled the hazard flasher and reconnected the brake switch. With that combo, my brake lights are constantly on, but dim. Next step - start pulling individual wires from the C305 connector. If I don't have hazard lights, I won't miss them much. In over 30 years of driving I've only used them a handful of times.

Pulled the connector off of the brake switch. All appears right with the world now. Will see if it continues to behave while I purchase a new brake switch. Something in the back of my little brain is still bugging me though...

Another clue. Never noticed before, but with a new fuse, the brake lights are on. No matter what I do (press brake pedal, turn on/off headlights, turn signals, hazards), they stay on. If I turn on the hazards, they work. But if I turn on the turn signals while the hazards are on, the hazards 'freeze' on and stay on. From that point on, the hazards, when turned on, do not flash - you just see the dash indicators on solid. It took some time, but after all of that testing, the fuse finally blew as I pulled out of the gas station. Will check the brake switch itself later this morning, but I can't believe that this switch by itself will cause the fuse to blow.