Jump to content

1974 RD685 Dump. Please help with frame and jake issues


nedly05

Recommended Posts

Earlier this year I reframed a DM. took weeks but I found totally rust free double frame chassis with trunnion and 4 crossmembers.Paid $1500 at the scrap yard. We took mixer off back. Removed front bumper ,fuel tank and battery box.Supported engine at front engine crossmember.Transmission w tranny jack.Cab back w scissor jack on top of tranny.Removed hood.We slid frame rail out from back on one side at a time.This allowed us to keep radiator on,A/C chrged and disconnected very few wires.Replaced crossmembers as we went.Took two days to do both rails with no fancy equipment.After everything from back of cab to front bumper back bolted tight , we rolled tandems where they belonged. Marked holes ,drilled and went back with body bound shoulder bolts.Replaced crossmembers in correct location. Quite a bit of drilling,but not impossible.Mack dealer had quoted $8000 for frame rail each side and $650 for each crossmember.Without finding a solid donor frame rails and crossmembers I would have been forced to "scrap" my DM. While tandems were out, we replaced springs,pads,wheel seals,brakes.Very Very easy to do this heavy suspension work w tandems out. After two weeks in the shop ,we had a very solid truck for little $$$ good luck!

Link to comment
Share on other sites

yup, that frame is junk. you should just sell it to me cheap haha joking. you should measure it up and call PG Adams. they are reasonable on rails, quoted me around 1300 bucks for 4 10 foot pieces of frame rail at Springfield. they are right across the border from us in Vermont to.. actually lookin for a tandem set of Mack air ride rears mysel at least 4.00 ration or less. id like to make the R609T im buildin a tandem with the 300+ and 10 speed roadranger.

post-6-0-64947600-1408238925_thumb.jpg

Link to comment
Share on other sites

Anyone have any experience with pg adams? Theyre about 1.5hrs away. Im going to talk to bruce at global truck traders tomorrow and see what he has available. He's about 45 minutes from my sister, might have to load up the family and go on an overnight parts run!

Link to comment
Share on other sites

Just saw the pictures. Yeah it's shot. Cut offs are usually just the rears and suspension with some frame rail left in front and rear of the setup. It comes down to how much you're willing to spend and your intended use of the truck. Anything cane be repaired or replaced but it comes at a cost. It's just those rails can not be repaired it's too far gone and need replaced Call up pg Adams since they are close and get a quote. They can even punch the holes. I know they'll prob ask you for the old one first to locate on the new ones. If you go further with this and new advice they're are quite a few guys who have re-railed trucksmon thisnsite. So don't hesitate to ask questions to get the job done right.

  • Like 2
Link to comment
Share on other sites

I have to measure the good frame today and see how much there is behind the cab. What would I need to be able to mount a single 23K rear axle? I'm thinking of swapping out the rears for 23's and the fronts for 12's and just cutting the bad frame off and just making a little single axle tractor out of it. Boy wouldn't that be a change from the beginning!

Link to comment
Share on other sites

id try to find good used frame rails.Used rails are usually cheap and almost a throwaway item at truck salvage yards. If im not mistaken ,the new frame rails from PG Adams arent going to be drilled unless there is a detailed shop drawing provided for each rail.Obtaining the shop drawings from mack would be impossible.Trusting myself to provide drawing accurate to their requirements would be difficult. You could order rails and use you old ones to "template" drill the new ones. Not fun but do-oable.You could go back w hucks or body bolts.

Link to comment
Share on other sites

The guy I bought the CH from doubled the rear part of the frame when he was setting the truck up. He said they have a guy that will come out and measure, and when you receive your rails they are all punched out. I haven't taken the time to call around about used rails yet, maybe today.

Link to comment
Share on other sites

you want to use huck bolts or grade eight fine thread nut/bolts if you go that way. You can order them with or without holes its just a lot more expensive.

Read through this thread from last year-

http://www.bigmacktrucks.com/index.php?/topic/22689-359-peterbilt-frame-rails/

I thought the holes were drilled with a special tapered bit and u used frame bolts to match..

Link to comment
Share on other sites

Hi Nedly , I see you over to HEF over the years. I guess Im the dumb redneck here , but I have had Mack dumps with rails in that shape and we weld, patch , drill bolt , gussett and whatever it takes to keep it hauling. I had a R dump truck and one time we were dumping a way to large load of clay over a hill and the frame broke in half. We bent the truck back into shape with the excavtor plated the frame inside and out drilled the shit out of it and bolted it. Truck hauled for 5 more years until motor blew. Go buy yourself a mag drill and some plate steel and fix it up. GOod luck. doug

  • Like 1
Link to comment
Share on other sites

Hi Nedly , I see you over to HEF over the years. I guess Im the dumb redneck here , but I have had Mack dumps with rails in that shape and we weld, patch , drill bolt , gussett and whatever it takes to keep it hauling. I had a R dump truck and one time we were dumping a way to large load of clay over a hill and the frame broke in half. We bent the truck back into shape with the excavtor plated the frame inside and out drilled the shit out of it and bolted it. Truck hauled for 5 more years until motor blew. Go buy yourself a mag drill and some plate steel and fix it up. GOod luck. doug

Not saying that can't be done, to each his own. I feel more comfortable with no more than one or two minor fishplates. That frame is cracked on the bottom flange where is was weled once before, its got so many holes its like swiss cheese, and on top of that its spread from rust. It looks like an 1-1/2" or more above the trunnion. No matter what how you to try to patch it up with plates and welds, that frame is going to rip itself a part because of the rust. To get the rust out you have to take off the outer frame or cut the top flange off, clean it , the reweld it back in. Thats a lot of work. I've done this and part way thru wished I would have gotten new rails. You'd be further ahead with new rails.

Plus, the matter really doesn't concern our opinions or how we feel. So you pull into a chcken coop and automatically the trooper or inspector is going over the truck with a fine tooth comb because of its age. Now he sees 4 or 5 repairs to the frame when he's on his creeper. What else can he find? What if your repairs don't work correctly and cracks spread past the plates. IMO why give them any reasons for a hassle,fines, or an out of service tag.

Link to comment
Share on other sites

Hi Nedly , I see you over to HEF over the years. I guess Im the dumb redneck here , but I have had Mack dumps with rails in that shape and we weld, patch , drill bolt , gussett and whatever it takes to keep it hauling. I had a R dump truck and one time we were dumping a way to large load of clay over a hill and the frame broke in half. We bent the truck back into shape with the excavtor plated the frame inside and out drilled the shit out of it and bolted it. Truck hauled for 5 more years until motor blew. Go buy yourself a mag drill and some plate steel and fix it up. GOod luck. doug

This is originally what I had planned to do. I was going to try to clean the frame the best I could with an air hammer and sledge then weld up the cracks and grind them smooth. We have the other two tandems, and two single axles so I really don't see it getting run as a dump. I could still make a tractor out of it and look for a small lowboy, like a fixed neck 25 ton or something. I would feel better about doing this if it had a 300/jake but oh well. Ive tried to sell it but no one seems interested but the exporters...

Link to comment
Share on other sites

  • 3 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...