Lmackattack

I converted my RS700L from manual to power sterring. I had to locate a pump,sterring box, resivor and lines. also needed a diffrent sterring shaft as it was to long or short with the new power steering box. I had to drill a few holes in the rail to mount and make a few large washers to get it flush on the frame rail. Not a bad job to do one weekend. Trent

and at that rate just keep it stock as the 12 speed was one of the first Mack air shift boxes that worked well. One thing I have never heard was if the clutch packs were better on the 12speeds vs the 9 speeds

FJH will know more about the problems in 04 but if I recall low power, Elictrical issues and Turbos? Turbos were on back order all over the place> I recall many had to wait 2-3 weeks to get a reman turbo. Many Mack Shops would over stock them if they cold get their hands on them and try to keep them off the "system" so they would have them in stock to support the local owners. It was not a mack problem but the turbo MFG was making them look very bad with no spare turbos. Electical troubles, Derate, trucks just shutting off, Not good and around here,lots of old mack owners went to other truck MFG soon after. Low power from emission issues. the engines would just start to come alive and pull then you had to shift. No throttle responce. it was like driving a large truck with a gas engine... this was my experince with the 04 models

I had mack boots about 10 years ago. I had both the black and tan leather. came in a green/black and red box had the old Mack logo with the "correct dog" on the emblem. they also lasted me 3-4 years before they were worn out. I used them every day at UPS working the docks walking on steel grates. Havent seen the new boots

hmm. on all the air lock power dividers I have used all you had to do was get some slack in the drive train to have it release. If I had it in and was going through mud then exit on to a street, the PD would unlock as soon as I let off the power or the truck coasted a little.(switch in the off position) Backing up will also do the trick but I have never had to as long as I unloaded the stress on the drive line and was not in a turn.? most times I turned it off 10' before I hit the pavement unless I needed it to get out. A few rules I have learned and told about with air power dividers..... never put it in with the tires spinning Most times the truck should be stopped or rolling in a straight line at slow speeds to put it in. dont drive on pavment with it in turn off before you reach hi speeds. dont put in at high speeds. tire size across the axel is important but hurb had just pointed out a great example that I did not know about mack power dividers.(thanks Herb)

Lets see. 1st you have the hi lo range shifter that is used with the clutch packs then you have the Low Low "dash switch" to use the lowest gear in the box. then you have the Reverse sshifter. all of these would have to be figured out in the shift pattern. Even if you removed the clutch packs you still have to find a way to get all the gears to slide around to enguage or not enguage. Money talks but its not really worth it to get 2 sticks from it as it works pretty darn good as it is. I always say its one of the best boxes Mack ever put behind a maxidyne.

10-4 fred. The 440 V8 at the yard holds around 26-28PSI. I think its a 1991 model? on a good pull I figured it should be close to that psi?

at one time the gold dog was to show the truck was 100% Mack drivetrain. I think that changed in the mid 80s? I herd Recently it has been brought back to represent a 100% mack drive train?

you dont have boost! 22 psi is a low side I think 25-30 would be what you shoul see. My straight 6 285 will pump out 28-30PSI in the cold. this is with the pump turned up a little.

I have yet to see a air shift 12 speed converted to a 2 stick. I dont think they were ever set up for manual linkage so it wont work. The older 6 speeds had the shift cover do all the work in the aux box so it could be manual or air depending on the cover you installed. I like 2 stick transmissions but I think the 12 speed with its clutch packs and short splits that work the aux box is beeter suited with air. let us know if you find more info on this...

I like how steep of an angle I can get my frameless and never have to shovel stuff out but then again always liked the safty factor of the 1/4 frame. as long as I dont have a frame trailer ,,Im all good.

if that pin broke that will be the first place to start. depending how long its been broken will depend if it wore down the pads and trunion bushings

I see one small problem.. We need a few pics of this project!!!!

It can be a number of things Worn pads, worn trunion bushings can cause the rears to walk. also bad control rods can add to them walking more. do the springs slide side to side? It could also be a bad end cap that has let a spring wear into the metal. The 2 control rods (one from the top of each diff housing to the trunion/crossmember) hold the diffs upright and control the torque input from the driveshafts. the 1 control rod on the rear rear diff is there to help hold the axels from walking. All the trucks I have seen had only one of these rods and it was on the rear rear axel. If this rod is worn out it will also cause the axels to walk. that rod was intended to help keep the axels in place on hard turns. Trent

I need to get my Dump trailer painted but I need to get the sides up about 6" I Figure I should add the sides first before I go and blast the traler for paint. looking for a 6" tall / 3" wide by 20' long. could be in 10' sections but need a total of 40' prefer used as its cheeper. can have some dents as it will get beat up anyways. if you are close to Chicago and know of any let me know. Also been thinking of finding a used 36" ablebody sleeper to put back on the truck. Mine had one from the factory but someone removed it years ago.. a few winter projects for me.... let me know Thanks Trent Chicago IL

wow .. thats a project LOL!! i wish you luck with it. thats alot of things to get lined up right. It sounds like you will be better off making some of the mounts rather than trying to get the diffrent parts to work for you??? regards Trent

If I recall correctly a R700 mount is a little diffrent than a 73+ RS700 mounts. as the later RS cabs sat higher above the fram than early models. same with Valueliners as those cabs also sit higher. As rob said the RS600-valuliner and later RS700L all had straight rails. the diffrence could be the mount or where the mount holes were drilled. I think most of the later cabs used the same style but they could be a little diffrent depending on the model of the truck. simple way to check cab hight is to look at the back of the cab. if the cab rear wall is about flush with the top of the frame rails. that could be a standard R model. if it sits about 6" above the rails the cab is "raised". Early Fuel tanks also used the front or rear or both cab mounts as a support so that may come into play? are you converting a R600 to a R700? Trent

Rob next time you see a frameless end dump look at the trailers 5th wheel plate. it will have a pivot mount for the hyd hoist and a pivot for the uder carrage beams. becasue of the 2 pivot joints on the plate and the 5th wheel pivot it would be a scary mess to raise or lower the trailer. So what you do is Block the 5th wheel to prohibit its movment. With it blocked now the trailer plate has a solid surface to let the hoist and beams safely work to "inchworm" the trailer when dumping.. most if not all Frameless and 1/4 frames need to be used with a blocked 5th wheel. I have blocked mine as well and did the fab work myself. I have a place on the side of my frame rails under the fuel tank straps that I put mine when not in use..

You can use R model Exhaust hangers and then fab up the exhaust from pipes found online. I was going the route of dual stacks but went with a single instead. What I did to get dual stacks was this. pipe came up between the frame rails to a "T" then the pipe ran across the top of the fram to each stack. Worked good but I went back to a single.. Trent

post a pic of it here and it may drum up intrest. also truck paper.com has a listing for old macks. they dont draw in alot right now with the economy in the tank. i bought both of mine for $500 not runing and $2000 running. I see alot listed for 1-2K depending on condition... rust is the biggest issue with the steel cabs

cement trucks and military

As far as looking at the outside its hard to tell if it has a v8 or not the early R600 models had an option for V8s then in the late 60s I think they only came in the R700 or RS/RL700 models. If the truck had a V8 fromthe factory it would have had a V8 emblem on the hood. on thing to look for is if it has a single stack. alot of the bigger V8s used a 5" exhaust where the Inline 6 had a 4".if it had twin stacks it will be harder to tell as you can run 5" from the turbo to the T pipe under the cab and 4" from the T-pipe to the mufflers. The Stock E9 V8 macks were pretty quiet even without mifflers. I have driven a 440 and 500. the ones I drove spun to 1900RPM and pulled pretty good. you could keep up with new trucks of the same HP all day. the company I drive for had a 2002 pete with a 550 cat and the 440 mack would walk on it up to about 60MPH.

You need to find the torque rating for the 5 speed spicer.If its as old as the 673 it will likely not have the raing that the maxidyne can put out. It is a rule that the older 2 countershaft Mack transmissions are stressed with the maxidyne high torqe engines. If its a toy it wont be a big issue. if its going to do some offroading the old trans will not like it with all that gear reduction and high torque. the older 5 and 6 speeds are direct drive the newer 5-6-7-8-9 speeds are overdrive(a very fast OD) so fast that you would likely need to put slower rears in to slow the truck down. If you looking for a good on/offroad for a old military truck here are the options I would do. 237-285-300 Maxidyne>6 speed> 4.17 (or slower rears) good for about 62MPH 300 Maxidyne>7 Speed> 5.73 rears (or slower rears)good for about 62MPH 350 Econodyne> 8LL > 4.17 rears (or slower rears)good for about 70MPH Im sure others could add some options.

The thermodyne was a Diesel commonly used in the 50s. I dont recall what year production started but it could have been in the mid 40s. It was a engine model term used to discribe the engine series. they commonly came in 673,711 CID some turbocharged some Natural asperated. They needed to be kept in the high RPMS to pull good. The Maxidyne was the engine that came out in 66-67? High torqrise. In its day it was a power house and a blessing. you went from around 180HP,600TQ to 237HP/900TQ and only needed 5 gears to pull the same load a thermodyne with an 18 speed needed. Maxidynes came out shortly after the R models were released. the first Rs had Thermodynes. Some have recently said the last few B models had Maxidyne test engines in them? Econodyne was another version basicly a copy of the maxidyne but needed a few more gears to get the job done. they had a little more HP but had a little less overall TQ HTH Trent

max RPM with no engine load was 2300 Max RPM with load was 2100 you can spin them to 2300 But I think most will agree its better to keep it at a max of 2100.