Since my boy is now a racer, we need another tow rig. Going to convert my '86 D-150 (318/Auto) over to big block power to do the job. This truck will be hooked onto an open 18' steel/wood deck trailer towing a B-body 80 miles (roundtrip) to the track maybe 8-10 times a year; plus occasional trips to the local tavern with my bride.

I snagged up an '81 Dodge RV with 61,xxx miles on the odometer. 440/long-tail 727. Just doing some really basic stuff to the 440 (reseal, headers, Performer RPM intake, 600 Edelbrock, maybe a cam for towing if anyone has any ideas) as well as converting it to an 8 3/4 with 3.55's. Of course, I'll add a large auxiliary cooler to the trans (and maybe the engine oil too?).

My questions really center around the transmission.

Research tells me RV-spec tranny's should have some good stuff already (4 pinion planetary's, extra clutch, etc.).

Any recommendations on internal upgrades or just clean/freshen/replace what's already in there?

How about a shift kit?

The converter that is currently in the transmission has a large ring gear but also has a sticker on it that says "low-stall".

I suspect they used these to get these giant bread-box lumbering barges moving?

So, maybe the converter is perfect for the application?

Any other thoughts/concerns I'm not seeing?

The transmission does have heavy duty internals.while apart I would put a transtar rv converter in it.

I have a 74 Ramcharger that's a factory 440 truck and in the last few years I've driven it over 800 miles. It's fun, loud, all stock except for suspension with 3.54 gearing in the D60/D70 axles with 33" tires. I'm averaging 6.8mpg. If I was to build an older dodge truck to tow with, I'd use a 360 magnum block and make it a 408 stroker.

i would recommend a TF-2 shift kit.

That or at least raise fluid pressure cheap tighten up shifts

Those 33" tires are what is killing your mpg. It takes a lot of throttle to get them rolling. Then, has your speedo been calibrated to the big tires?

So is a 408 stroker motor any more fuel efficient then a 440 with a good towing cam?

I've pulled a car trailer with a factory 440, and I've pulled that same trailer with a 360 in a truck, the 360 did OK, but didn't hold a candle to the 440 truck, and both got the same gas mileage pulling that trailer (about 9mpg).

I've never had a 408 Stroker, so I have no comparison between it and a 440.

All good stuff fellas - keep it coming

Think I should call Comp for a cam recommendation or will that be waste of time?

If towing no .u got the best cam possible for that.

Deep trans pan. Coated headers to control heat.

I’d run a larger vacuum carb. A 600 is smaller than a lo po 440 had. A tq would be good and is what factory 440 trucks had for years. I’d want as much power as I could get when towing. Guys can do what they want, argue this all they want, but a bigger carb doesn’t kill low end like is claimed. The secondary’s will come in as needed. That’s been my experience running a big carb after a small one and the seeing the results.

I'd consider swapping to an 8 lug D60 rear and upgrade the front brakes to 8 lug as well. The 440 won't have trouble moving the trailer but the bigger brakes and stiffer tires will help control things better.

Sounds like a lot of work for something the 318 would handle….. this ole beater made a ton of treks from Aberdeen to TVD open trailer with race car 318/727

I agree. For that little use the most I would do is install some 3.91 gears. If the trailer is set up the way it should be with brakes on both axles it will stop just fine.

No farther than you are going you could spend some money on the 318 or swap in a 360, Unless hills are involved. A 408 Stroker would give you big block torque in a small block package provided the heads could move enough air.

A 360 magnum with hyd roller cam would likely do just fine for a lot less money.

I love my big blocks but don't look forward to that much work any longer.

Man I dig those Mirada wheels on that truck - after I swap mine to 4 1/2" BP I'll have to hunt down a set!

The reason for the swap is the ol' 318 is really tired and the trans is some kind of version of a 904 - just figured since I had all the parts the swap made sense.

Torque for that application is King, as well as keeping highway RPM in the meat of the torque curve, usually around 2600-2800 RPM.
MPG benefits when using as little throttle opening as possible while pulling.
While my 408 made very good TQ in a Duster, it didn't compare to an RB.
Thermoquads are great in that application, 2nd best a vac-secondary.
I'd use the existing MH converter. Shift kits are a good thing, as they reduce the shift overlap; doesn't need anything racy.

Since the OP already has the MH 440/727 and the 318 is tired, the path forward seems pretty obvious.
Make sure you can cool it, and add an ATF cooler. I like deep pans on everything.

Mike Jones has a grind specifically for the motorhome big block engines. It ain't cheap, but you get what you pay for. If I was to make one change other than what you have mentioned it would be the cam. The smallest lunati voodoo would be a distant second choice.

No more than you will be driving it though there is nothing wrong with keeping the oem cam if it is in good shape. Won't get quite the same power but it will be well above what the 318 was on its best day anyway.

Trans cooler and shift kit would be on my list as well. OEM low stall converter is good for this application. It will help keep the revs down and give a little better mileage since it is likely not a lock up converter.

ramp truck , close thread

LOL - You build me one 'Dad and I'll put Brownie in the weeds!

How do I find out about Mike Jones? Did a search and the commonality of his name about put Google into a tailspin...