So ive been on the hunt for a heavier truck to replace my f650 for a while now. I found a 1995 mack rd694 p with 170 k miles on it looks super clean has air to rear etc. wondering what the thoughts are on this trans though. Its a maxi torque six speed mack transmission. It has hi low 1st and then straight shifting through 5 th gear. Also has hi lo reverse. Seller said it was a cat motor butwhen he showed me the pictures it was a blue motor with mack written on the valve cover. Thinking its a mack e5 motor since he said it was around 250 hp. My question is how is this engine trans combo. I want to buy a 20 ton tag to pull my kubota ex and bobcat skid as well as my pc 120 ex. Thanks
Does it have to be a single axle? That sounds fine for a single axle truck, but a 120 size machine and the weight of a 20 ton tag is going to be a load, I really would want at least 300hp. What are the specs on your 650?
Yea its gonna be heavy but i do mostly residential work so a tandem is too much truck for my needs. My 650 has a 210 hp cat and juice brakes witha. 7 speed trans. I pull my 12k lb mini and it does ok but its really tough on the truck and its not the safest thing with juice brakes. Also really lacks a low range in first. I wouldnt be pulling the 120 everyday but it would give me the option of moving my own machine as well as open up some work opportunities.
I drove a Mack 10 wheel dump for a couple years back in the 80s. It had a 237hp Mack engine with the Maxi-Torque transmission that is exactly as you describe. A 5 speed stick with a secondary stick that had High, Low and Reverse on it. You can run through all 5 gears in any position of the second lever, but you could only shift from low to high in First on the primary lever. I never encountered a time where I couldn't move the truck with the heaviest load. Top speed was about 60mph, and the only downfall was becoming gearbound on occasion on hills. The advantage was you aren't shifting all day long. I was told this one time, I don't know how accurate it is: A Mack horsepower rating on an all Mack drivetrain is measured at the wheels rather than the flywheel as on other trucks so it is realistically higher than posted. I asked this because I drove both a Mack and an Autocar with a 237hp 6/71 in it and the Mack would run away from the Autocar with the same load and I wonderd why. Again, I don't know how accurate the answer I was given is. I think the truck would be adequate, but if you are in a hilly region you might take a little extra time and work to get where you're going.
Oh ok thanks for the clarification. Talked to the guy selling again today only problem i have is the lack of air conditioning anyone know what kind of numbers they get to add a/c to these trucks is it even possible? Its an e5 motor i believe called h and h mack and gave them the vin. Supposedly guy is going to call me back with the specs.
Wow, New Jersey without air conditioning. Even Lucifer can't handle that...
I would not attempt those numbers behind a single axle dump unless its extremely flat and dry were you live. I pull a 24 ton tag on daily basis with either a peterbilt 359 or 379 one has a built bigcam 400 (475hp) on the dyno w/13spd the other is a c12 425hp w/a 18spd. The trucks do good but its a lot of weight on the hills. I have 30-35000 pounds on the trailer depending on the combo. I had a SA f650 with 6spd and a 300hp c7. I pulled 10 tons behind that and I would not anymore behind it was alittle bit scary at times.
We use another contractors SA pete to move it and its at the limits but its not bad. Found out from the dealer its a 260 hp motor. Most guys around here use single axles with 20 ton or better trailers. One of the big guys by us uses a sa pete with a tri axle tag to move his dozers etc. Its not an everyday thing if it was i would be looking for a new machine and a low boy.
Look at a Red Dot system for adding A/C. They work well but I don't have any idea of cost.
I second the red dot. I have one and it works well. As far as the motor trans combination it will work. I have an e6 350 with the same trans in a tri axle. it is horrible to drive but I am used to 400+ trucks with 15 or 18 speeds. You cant kill that old mack. It always pulls whatever is put on it... I have been over loaded to 88,100 in the bed and it pulled it. It wasn't happy and neither was I when I got to the dump and weighed. I wouldn't pull that weight on a single axle but that mack your looking at will do what you need. You WILL hate the lack of power feeling.
Yea i know im not going to set any world records but hopefully it gets the job done. Going to try and look at it thursday ill let you know how it goes. Any advice on what to look for?
Obvious leaks on trans and engine, blow by. Not sure if smaller trucks had the issues with the trunions rotting, the big ones did so it is worth looking very expensive. Breaks, tires, kingpins. Unusual tire wear. Frame cracks especially behind the cab again not sure about the small trucks but I have seen issues with the large ones. I always pick the trucks apart and tell the owner then make an offer. freeze plugs rotting were an issue especially in the head again e6 engine.
Ill take some close ups and post them here. Thanks again guys coming from little trucks to the big leagues dont want to get screwed.
I dunno, I tried hauling a hitachi 120 with my ford 800 7.8 motor, 5 speed w/ a 2 speed rear and was not impressed. Topped out at 50 on the dead level. Trailer is a towmaster tk40. I'd be lookin for something with at least 300hp, and a short tandem preferable just for the added brake axle.
A 7.8 is also only 210hp i looked at one of those also they dont have much power wise. I really only move my small machine on a regular basis and the big machine would only be moved locally back roads nothing over 50 ussually.
The best part about that f-800 is the mileage. Loaded to almost 50k total weight, I can get a little better than 12 mpg. I don't own the 120, I was movin it for a guy. What I do move on the regular are a gehl ctl 70, a deere 550g, a takeuchi 053fr, and it handles those well. Eventually I'm getting something bigger be it a roll off or a triaxle dump and they are going to be set up for the trailer so I can get a bigger hoe, prolly a 160 and move it myself. I hate having to wait on someone else to move something. Its not the money that it costs its the sorry, I'll get you tomorrow, or maybe sometime next week stuff.
7.8s went up to 270 HP and that model pulls really good for its age in my experience. They also seem dead reliable.
It sure feels like more than 210, honestly I thought it was about 240 by feel... but all that really matters is that it does what I need efficiently. Had the truck 3 years now, and dead reliable would describe it well. Its kinda why I haven't upgraded already, passed on a nice older freightliner tandem with a 400 cummins cause the bed was only 12'
The 7.8 i looked at was owned by a friend he said it would pull a house but top speed was only about 55-60 which is a problem when im moving dirt. Im in the same boat with my f 650 except when i put the mini ex behind it the truck wont go much above 60 nor do i feel comfortable doing it.
Well after looking at the truck we decided its a little too old. Found some ex nydot trucks with aluminum bodies for 25 k look pretty good in pictures going to take a look this week. Also found a sterling actera with a mercedes 8ll trans.
Called about the acterra today ran the vin. It has a 280hp mbe 900 with an 8LL behind it air conditioning, engine brake, aluminum wheels basically everything i want in a truck. Still on the fence about this motor having the guts to pull my machines. Or theres the 350hp ex nyydot truck with no air or engine brake. Which way would you guys go and any thoughts on the mbe 900?