Pintle hitch modifications

[Acoals]

Looking for some opinions or ideas here. The truck is an L9000 dump, I pull an tandem axle air tag trailer that weighs up to 50,000lb with the excavator on, including pretty substantial tongue weight; about 15,000lb. When I got the truck, it had a swiveling pintle that is rated for 30,000lb as near as I can tell. I am trying to upgrade the pintle to a fixed setup that is rated for 45 ton. The trouble I have is that the holes from the old unit obviously don't line up with the new, and there really isn't room to move the new unit to a different place. I am a bit uncomfortable having to many holes to close together, but I really don't want to take the body off and completely rebuild the tail of the truck. The plate on the truck that the hitch bolts to is 1" plate.



The white dots are the location of the holes for the new hitch. The old hitch was held on with 1/2" bolts. The new hitch has 3/4" bolts. If I moved the new down a bit, the top holes would overlap the upper holes on the old, except about 1/4". The only way I have to cut an overlapping hole like that would be to cut with a torch, which isn't terribly precise. Not sure if that is acceptable with 25 ton floating around . . . ?


What was in there:



What I am planning to put in:

 

[Truck Shop]

1" plate, that's heavy. IMO drill it first then plug weld the old mounting holes shut and
grind flush. That way your not trying to drill a hardened area after welding. At 1" thick
I seriously doubt it's going to have a failure from cracking, most are built from 5/8"
material.

 

[materthegreater]

Would a mag drill with an annular cutter work for drilling the overlap holes?

 

[Acoals]

Would a mag drill with an annular cutter work for drilling the overlap holes?

I am not familiar with mag drills or annular cutters. A quick google search just informed me they are pretty pricey. They would probably work better. Almost anything works better than hand drilling 3/4" holes through 1" plate with a Millwaukee magnum hole shooter ...

 

[Acoals]

Would an annular cutter bit work on a electric hand drill? A 3/4" spiral drill bit through heavy plate like that is pretty brutal, but I don't see a hole saw working either.

 

[materthegreater]

I am not familiar with mag drills or annular cutters. A quick google search just informed me they are pretty pricey. They would probably work better. Almost anything works better than hand drilling 3/4" holes through 1" plate with a Millwaukee magnum hole shooter ...

See if you can find one to borrow. It's like having a drill press that you can mount to any steel surface. Annular cutters are far superior to twist drills.

 

[materthegreater]

Would an annular cutter bit work on a electric hand drill? A 3/4" spiral drill bit through heavy plate like that is pretty brutal, but I don't see a hole saw working either.

No, they have a special shank that won't work in a 3 jaw chuck

 

[materthegreater]

I drilled these 1-3/8" holes in 1-1/4" steel bar in about 10 seconds each.

 

[Vetech63]

God, I hate trucks LOL

 

[1693TA]

I too have a Hougen mag drill and use it often when doing things in the shop. Far superior to hand drilling and very precise holes. Kinda like mounting Peterbilt air bag mounts where you drill through the bottom of the frame rail upward.....



Most mag drills use a 3/4" "Weldon" shank to drive the annular cutter. There are adapter chucks available to operate normal twist drills but their use is limited and none I've seen are very accurate.

 

[1693TA]

God, I hate trucks LOL

I hate them SOB's too.

 

[Old Doug]

God, I hate trucks LOL

You must belong to the Mennonite clan were they have trucks for work but use horse and buggy to get around. Sometime your in town stop at a shop were they work on cars,pickups,vans and suvs and see just how much harder they are to work on then you will find trucks are not so bad.

 

[Old Doug]

I hate them SOB's too.

Same church that Vetech63 belongs to?

 

[Vetech63]

see just how much harder they are to work on

Precisely my gripe.

 

[Old Doug]

Looking for some opinions or ideas here. The truck is an L9000 dump, I pull an tandem axle air tag trailer that weighs up to 50,000lb with the excavator on, including pretty substantial tongue weight; about 15,000lb. When I got the truck, it had a swiveling pintle that is rated for 30,000lb as near as I can tell. I am trying to upgrade the pintle to a fixed setup that is rated for 45 ton. The trouble I have is that the holes from the old unit obviously don't line up with the new, and there really isn't room to move the new unit to a different place. I am a bit uncomfortable having to many holes to close together, but I really don't want to take the body off and completely rebuild the tail of the truck. The plate on the truck that the hitch bolts to is 1" plate.

View attachment 282142

The white dots are the location of the holes for the new hitch. The old hitch was held on with 1/2" bolts. The new hitch has 3/4" bolts. If I moved the new down a bit, the top holes would overlap the upper holes on the old, except about 1/4". The only way I have to cut an overlapping hole like that would be to cut with a torch, which isn't terribly precise. Not sure if that is acceptable with 25 ton floating around . . . ?


What was in there:

View attachment 282143

What I am planning to put in:

View attachment 282144

That maybe 1" plate but it isnt very wide it would need alot of bracing. Is the new hitch one that uses a pancake for cushion?

 

[1693TA]

Same church that Vetech63 belongs to?

Every Sunday and Wednesday evening prayer service. Every time I drive one of my Mack trucks, I think once again: "One Azzhole Looking at Another".

 

[Acoals]

That maybe 1" plate but it isnt very wide it would need alot of bracing. Is the new hitch one that uses a pancake for cushion?

There is a cross brace on the inside, about midway between the lower bolt holes and the bottom of the plate. There might be one in the upper part as well, I am not sure.

 

[1693TA]

There is a cross brace on the inside, about midway between the lower bolt holes and the bottom of the plate. There might be one in the upper part as well, I am not sure.

Usually is, or should be. Seen and replaced several that were either bowed in, or out from the stresses imparted without the bracing. 1" plate is common around the oil fields of southern IL but lighter up north for some reason.

 

[Old Doug]

My truck had a 1/2 plate witch may have worked ok on a c70 but they didnt brace it. I stayed up the night before i went to buy it building a tow bar for my pickup. When i got there the plate witch was 18" long was bent out at a almost 45 but it was steal secure on the truck . I built a new one out of 3/4. The bad thing is were i want the pintle hitch it needs to be close to the reciver hitch to be low enough for what i want.

 

[Truck Shop]

Drill it to 1/2" then finish with a 5/8" and 3/4" Car Reamer. Keep sprayed with
lots of cutting oil.