Overwhelming success owed in part to Moparts

I just delivered the biggest project I expect to have for my small shop and it was a massive success! Moparts members helped make it happen by offering ideas and suggestions in some of my posts.
It did try to kill me a few times but more on that in another thread.

A luxury car dealership has a very hilly lot where all the driving lanes are either going up or down and all of them are off camber. They maximized the property by benching as much of the property as possible but the service department is still split into four terraced mini-departments. To get to the body shop you have to drive into the lowest service department and make a hard right turn to go down a 13 degree ramp and through an 8'8" high opening.

Tow trucks can get around the property okay but they can't get down into the body shop with anything larger than a mid size car. To assist with moving cars, the store bought an 8,000 lb forklift and a wheel lift to go with it. That kinda works but the off camber bits have lead to the destruction of several GoJacks when dragging AWD cars and the forklift loses traction on the ramp.

I was asked to fix the problem.

My goal was to enable any single technician to retrieve any vehicle they sell or service with or without the tires. I wanted it to be safe, easy to use, require minimal training, and be reliable.

The solution was an old United Tractors SM80F tug like you'd see at an airport. This one was a bit different than most because it had lots of flat surfaces for me to work with. It met my requirements with assisted steering, assisted brakes, four wheel brakes, and dual rear wheels for added stopping power going down a wet ramp. The fact that it was rated at 8,000 lbs draw bar effort was a bonus.

Why so big? It's pretty easy when you break it down. Weight = tractive effort. Flat and level this thing is rated to pull 350,000+ lbs at 5 mph. Introduce a 13 degree slope and that drops to around 20,000 lbs when stopping and restarting on the slope. Make the tires and ramp wet from rain and you really appreciate the safety margin. When someone is dragging a 9,000+ tow (dolled up Super Duty 4x4 truck) down a wet ramp and an employee steps out in front of them the tug better be able to stop the load.

The tug is powered by a Ford 300 inline six, C6 transmission, 6.67 rear gears, and 3.33 planetary hubs.

The first thing I did with the tug was take it to Jiffy Lube to change all the fluids and flush the cooling system. Those boys kinda freaked when that monster drove in. After that, I replaced the carb, battery, plugs, wires, cap, rotor, air filter, and fuel pump (integral filter).


I made a series of modifications to the tug to better suit the intended use:
Added 2" trailer hitch balls front and rear.
Locked the draw bar pins to prevent accidental pull out.
Added a 3/4" steel plate grille guard behind the hitch.
Added 8,000 lb lifting links front and rear to accept the hook of a tow strap.
Added a front hitch camera with weather resistant monitor.
Added BIG vertical rubber push bumpers in front.
Added seat belts for both seats.
Converted to LED lighting for better gauge visibility.
Added a high amperage battery connection to the back of the tug.
Mounted a tool box with weather seal on the right front fender.

With the prime mover straightened out and able to drag cars I had to address cars that wouldn't roll. To address this, I grabbed a Master Tow 80" wide tow dolly. The fenders, lighting, wiring, wheels, hubs, and ramps were all removed. A folding landing gear was added to the tongue. Behind that I added a 7500 lb trailer winch. When using a tow dolly sharp turns will smash the fenders into the car your towing so I machined adapters to mount forklift wheels. The fixed ramps would drag the ground and slap the car when traversing the ramp so I built a new set that could be dropped in place when needed. To store the ramps I cut a small slot in them and welded a sliding barrel bolt (think gate latch) underneath. Steps and blades were added to the tug. To put the ramps away the tech carries them to the tug, stands them vertically on the steps, pushes them forward onto the blades, and slides the barrel bolt to lock them in place. Quick, easy, and intuitive. The ramps stayed mounted nicely on the drive down there.

Backing up a car on a tow dolly is nigh on impossible. To handle tight parking maneuvers the tech can stop the tug and drop the tow dolly on the landing gear. That allows him to turn the tug around, use the camera to line up the dolly with the front hitch, and push the car back into it's spot. It will be just like pushing back airplanes. The direction you turn the wheel is the direction the back of the tow will go.

With dragging a dead car addressed I had to take it a step farther and consider AWD cars with locked transfer cases and wrecks missing all 4 wheels. For those instances, I picked up a set of In The Ditch self lifting wheel dollies like you see hanging off tow trucks. The extendable axles and their carrier mounted nicely on the back deck of the tug. One wheel set and it's stand fit behind the axles while the other set was mounted on the left front fender. They do not impinge on driver visibility and the rear stand made for a nice place to mount the high amperage connection for the winch.

The wheel dollies and tow dolly had straps to go with them so I dropped them in the fender mounted tool box along with the winch controller and a 20' tow strap. As a bit of a bonus, I picked up a pair of jumper cables, put a plug on one end to match the winch power plug, and dropped them in the tool box. That turned the tug into a 9600 lb jump box so they can power up dead cars when necessary.


When I delivered the tug the parts manager (my primary contact) drove it into the service department and we were quickly surrounded by techs and service management. I presented the features and capabilities to the group. A few questions were asked and I demonstrated the solutions. There were no concerns presented that I had not addressed in the design. The techs were satisfied with the tug and dolly. I dare say they were enthusiastic due to the number of vehicles they get with locked transfer cases. Management was happy and I could see concerns evaporate as they studied the equipment and the Q&A progressed.

In all, it was a screaming success. The client has their concerns addressed, I learned quite a bit, and a tidy profit was made.

Looks real good and sounds like you covered everything needed. Way to go.

Interesting! Thanks for sharing.

Very nicely done!

thank you for sharing how that project turned out !
a pic or two of it in action would be a bonus.

The plan was to take it to a huge parking lot nearby and do a demonstration video dragging my truck around. After the effort it took to load the dolly and nearly killing myself getting the tug up there I had no desire to repeat the process.

When I got to the client's store the weather was nasty and I was worn out from the 10 hour drive through the Texas Hill Country dragging a 14,000 lb trailer with no brakes. Only one deer was harmed in the process. Needless to say, shooting a video at that time was not in the cards.

My father was with the airlines for many years as an A/P mechanic for National Airlines and Pan AM. They actually called those tugs Paymovers.
Those tugs are very powerful for pushing out or pulling in everything from 727's to 747's.

The parts director at that store is a close friend of mine. We go back to 1986 and still chat on a regular basis. We used to race each other back in our high school days.

On one of our phone calls he was sport b!tching about the situation and I told him I could fix it.

Anyway, he and I took the tug for a drive around the lot. The steep gearing means 1st tops at a walking speed. Second will get you up to a slow jog. Topping out third gear gets you screaming along at 16 mph.

He drove the beast down into the body shop and turned around to take it up the ramp. About 1/3 of the way up he lifted his feet and the tug was slowly climbing the ramp at an idle.

That's when he whacked it.

Smashing the throttle to the floor the tug jumped quicker than any 9600 lb beast has the right to do and nearly lifted the front wheels off the ramp. it has leaf spring suspension but no shocks. I was VERY happy I had installed seat belts. After the giggling subsided we agreed that the tug made enough noise that you could hear if someone was abusing it.

This one was traded in at a forklift dealer by Gulfstream.

It is capable of moving a half loaded B52 bomber.


I wasn't looking for a tug this heavy. My eye was set on the 5,000 - 6,000 lb class. Those have the brakes, power assist, and tractive effort required. However, when this beast came up at a fraction of the market value and had all those nice flat surfaces, I had to do it.

See those plates laying on the back? Solid steel ballast.
See the thickness of the rear wheel opening? Ballast welded in flush.
The rear panel is 1" thick plate.
The rear fenders and front bumper are 1/2" plate.
Front fenders are 1/4" plate.
The unibody is made from 3/4" thick plate 14" tall.
Those big bulky front grilles? Solid cast iron.

My 2 ton floor jack can lift the front bumper but only takes about an inch of travel out of the rear suspension.

it will be "interesting" to see if that monster can be "damaged" [body wise] in the future. i kinda' doubt it, but ya never know......

That kind of thinking and execution would have made you an expert in any field.

I made a small addition to the tug. At the bottom face of the steering column in front of the driver is a label that says:

Rule #1: Tug doesn't care.

I pointed that out to the service director. Tug don't care.

Run into a car? Tug don't care. The body shop just got more work.

Hit a curb with the tow dolly? It might wreck the dolly or the car but Tug don't care.

Tow a car with a chain and pop the slack out of it? Tug don't care but you're going to rip parts off the car.


Each of those fat front bumpers have four 3/4" bolts holding them to the 1" thick steel plates. The stand offs are 3" diameter steel bars. A pair of 5/8" diameter bolts pass through each of the bumper plates, stand offs, and 1/2" thick front bumper of the tug.

The entire vertical rear face of the tug (rear bumper) is 1" thick plate.

If they hit something it's going to hurt something. A hard enough whack at an angle will lay over one of those big red bumpers but it'll take a really solid hit. You're talking major damage to a car and possibly taking a chunk out of a building support.

Thanks.

Nobody wants me as an engineer because I don't have a degree. I'm just a deplorable kind of person.

I feel your pain... Awesome vehicle, great job!

Very nice!!! Excellent job.

Every Vehicle Maintenance shop in the USAF has one of those. Ours were usually set up with a pair of 8D batteries and a series/parallel switch to jump start 24V systems, and we didn't have to worry about the dollies...

Perfect.

That is very cool, and I am glad it worked out so well.

I like the "Tug Don't Care" part because that is largely true.

is it fuel injected or does it have a carburetor?

It has a carb.
In fact, it had a manual choke carb that wouldn't run properly. I replaced it with a new carb equipped with a hot air choke. I found a length of brake line that fit the choke inlet and routed it down around the exhaust manifold. When the manifold gets hot it heats the tube. The little vacuum leak that draws on the tube pulls in heated air that actuates the choke.

That is probably not a bad setup. With multiple drivers it needs to be stupid simple and that is way better than a manual choke.

Well, how is it working out?

They haven't killed it yet!

The techs seem to use it more as a 9800 lb jump box more than a car mover. Still, they've had to move a few cars.

My contact down there sent me photos of them dragging a dead SUV with a locked transfer case off the upper deck of a transport. It had been loaded with a forklift. The tug pulled it down with very little effort despite the trailer going full cheese grater on the four locked tires.