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OK, I'm a long way from the drive train part, but let's float a hypothetical so I can have something to think about and look for.

Let's say I've got a 52 Suburban that I would like to have as a frequent driver, but occasionally, say 10 to 15 times per year, I might need to tow a 4500 pound trailer 500-1000 miles round trip. I would like to cruise comfortably at 70 mph with a little extra oomph just in case. Also might go to 10-15 shows per year with no trailer. Most trips will be along relatively flat highways.

In your opinion, what would be the optimum setup of engine, transmission and rear end gears. Is it possible to have empty cruising with good mileage or to have pulling power without being to doggish and poor mileage?

Thanks,

Robert

If you're not anal about strict originality I suggest a SBC with a 700R4 transmission and a 10 bolt or 14 bolt or a F#rd 9 inch rear with disc brakes all around. That would have the power to pull and the rear would be strong enough for the SBC and with gears in the mid 3s you could cruise at 70+.

If you insist on keeping 6 cylinders I would go with a 292 or 302 GMC. A 261 might be ok but would be a little light on power when towing. However, if you kept the bypass thermostat in place you wouldn't blow it up if you lug it.

I would go with a T5 transmission if you use a 6 and keep about 4.11 or 3.90 gears. Then you get overdrive to run 70 with but enough grunt to pull the trailer off the line.

That's a pretty heavy trailer, though, so if you think you would want a V8 go with it. Gas milage wouldn't be that much different. I would use an NV4500 transmission but that's because I hate automatics, especially when towing.

Big Chevy,

I assume by SBC you mean small block Chevy. I have access to a stock 305 with 30,000 miles on it and auto tranny (not sure which one). Never was impressed with mileage or power of any 305 I have driven. Price is good at $450. Should I keep looking for a 350? Would 3.73 gears be adequate?

I'm not interested in putting in a 6 cylinder at all.
I've hung around people all my adult life that have built street rods, but this will be my first experience.

Thanks Guys,

Robert

Is that trailer a barbecue wagon? I'm just guessing from your handle.

An AD Suburban has 116 inch wheelbase, and rear track width of about 62 inches. Stock it weighs less than 4000 pounds and is rated as a 1/2-ton truck. Length and width contribute to stability when towing and those dimensions are all a little small to be pulling a 4500 pound trailer at 70 mph. Smaller trucks are often rated to pull as much as 5000 but they are scary doing it.

I'm sure that trailer has brakes, but I'd start by planning to put brakes on the Suburban that would stop the trailer even if it's brakes had failed. Since the trailer weighs more than the truck, its always going to be marginal.

The GM 14-bolt comes in two versions, the smaller one (semi-float) has six lugs and brakes that are probably about big enough to do this job. And you definitely want good big disks up front. Ignore the 10-bolt, it isn't big enough. The full float 14-bolt or a Dana 70 would have bigger brakes, but are overkill for your truck.

Next step is the tires, you want tires and wheels rated for the max load including the trailer.

I start with those issues, because those things add quite a bit of weight, and the heavier it gets the more power you need under the hood even without the trailer. I'd pass on the 305 and look for a 350, or maybe go with a 383 stroker motor. Look at the later motors, the 5.3 seems small, but everyone I know who has one loves it, even pulling a trailer the size of yours.

The 700R4 will probably be adequate, but most recommend you stay out of overdrive when towing.

My 4200 pound (empty) 350 powered 3/4-ton pickup with a 700R4 shifts down to second so often when pulling a loaded trailer that I wonder if it would ever go into overdrive. But I've never tried either.

An automatic is a bad idea. I would go with an NV4500 behind a 292, but a 350 will work well, especially if it is RV cammed. LT 16" rubber would be an absolute must, as would a 4.10 diff ratio behind the overdrive, or a 3.90 behind a direct.

Old Sub,

Yes it is a BBQ trailer. The pit weighs 2500 pounds, the trailer is just a guess. It is a 12 foot, tandem axle with brakes, diamond plate floor, 15 inch wheels. Could be 3500-4500 total.
I would like to have four wheel disc brakes. Currently tow it with a '05 Avalanche or '04 Grand Cherokee and they seem to do OK other than the mileage, which is directly related to speed more than anything. But I would say they are close to their max weights regardless what the owners manual says. I have seen folks towing much larger trailers with their 1/2 tons.

That's what I'm scheming on. I hope to incorporate the Sub into part of the convoy.

Do you foresee any other problems?

Thanks,

Robert

Yes Robert, SBC does mean Small Block Chevy but 305?...well not THAT small my friend. 350CID or more if you have cubic dollars.

305's lack the power to do anything better than a good 261+ will do. My persoanl experience with OD A/T with a proper engine has been good pulling trailers up 7500 lbs over distances and mountains. Just depends on what you call speed and safety. In my book that means whatever speed you can do in the outside lane pulling your trailer. I hate those trailer happy idiots who think they have to run 75-80 in the inside or passing lane just because they can and endanger everyone on the road. Inconsiderate bastards!

Pulling your trailer with an Avalanche is probably better than doing so with the Cherokee, though I say that based on my assumptions regarding what those vehicles are.

I'm thinking the Avalanche is longer and rated for a heavier load. The Cherokee is likely shorter and less stable, at least when circumstances are more difficult, like being passed by a big truck, slowing going down a hill, running on a bumpy highway or forced to make a panic stop. I made that panic stop in rush hour downtown freeway traffic once. Only damage was my shorts, but it was scary and my heart beat hard for the next 15 or 20 minutes. I've not pulled a load with a 1/2-ton pickup since.

Pulling that trailer 10 to 15 trips a year is enough that you need to build your truck based on that usage. I'd suggest you think about the differences between that 1/2-ton Suburban and a 3/4- or 1-ton truck, and make sure your modifications make it closer to what that bigger truck would be.

I don't know how you could overcome the length issue without changing bodies, but using heavier stronger axles, with bigger brakes, will make a difference so start there.

While making it adequate to tow your trailer under most circumstances isn't hard, making it safe when things go wrong is the challenge. You can't eliminate every possible problem, but you can beef the truck up to make trouble less likely.

I'd put brakes on that trailer. Also, a load leveling hitch and upgraded sway bars on the suspension.

The trailer has brakes and is balanced very well. We've only pulled it twice with the Grand Cherokee, but many times with the Avalanche, and a couple of times with my wife's '02 suburban. Whenever I pull it with my F-250 power stroke you don't really notice it being back there.
I guess I'm trying to have my cake and eat it too. I'd like to have a cool, cruising Suburban for going to rod runs but also be able to incorporate it into the traveling barbecue road show. I would like to have it lowered a couple of inches or at least raked. I guess I could lower it with air bags, but didn't really want to go that route. Too much expense and potential problems for me....
Could I get by with a mustang II front end? I would like to have 4 wheel discs as well. What frame set up would you use, stock or something else?
I've been hanging around here a year and respect your knowledge and opinions. I only ask because I don't know enough about many of these things and would like to get it right the first time.

thanks,

Robert

I agree with Robert, my F250 superduty diesel will pull a house trailer, and it is automatic/with overdrive!

For many years I was against bumper hitch trailers because I have driven an 18 wheeler several million miles and I felt uneasy without air brakes and the stability of a truck. For many years I used an 18 wheeler to move my tractor which weighs 7000 to my mother in law's 90 miles in the Texas Hill Country. With fuel so high, I have started using my 06 chev 1/2 ton with a 4.8 liter and an electronic brake controller and a car hauler with tires rated at 3,000 lbs inflated to the max, and paying attention to tongue weight, and I am amazed at how stable it feels. And I get over 12 miles per gallon.