Towing math blues

[swissair]

If my math is right then my family of four will exceed the GVWR for my 1/2 ton suburban, even w/o including any cargo. After gathering all the numbers shown below, I take my GVWR of 7,400, subtract curb weight of 6,100 and tongue weight of 880 (30' Flying Cloud) leaving a max of 420 lb for combined people/cargo. That would mean no cargo and leaving one of the kiddos home alone. Wife said no on both counts. To make the numbers work on paper we'd be limited to a 23' Flying Cloud, but we want the 30 footer. So, here is my question for the pros - is there anything I'm doing wrong with the numbers?

If the math is good, then is there anything I can do to make this TV + AS marriage work? Will a high quality no-sway package combined with AS superior aerodynamics mitigate safety concerns? The AS dealer suggested that it would, but I'd like to hear from others. Here are the other numbers:

TOW VEHICLE
2007 Chevy Suburban 4WD, ½ ton, 6 liter V-8.
Rear axle ratio = 4.1
Curb weight = 6,100 lb
GVWR = 7,400 lb
GCWR = 14,000 lb
FAWR = 3,600 lb
RAWR = 4,200 lb
Owner’s manual says max trailer weight is 7,900 lb

HITCH
Class V-5.
Tongue weight carrying –600 lb
Tongue weight distribution – 1,000 lb
Trailer weight carrying – 5,000 lb
Trailer weight distribution – 10,000 lb

TIRES
Load index 108 (2,205 lb), but inside door panel says people and cargo should not exceed 1,304
Size – 20.5” x 8.5”

TRAILER
2011 Airstream 30’ Flying Cloud.
Hitch weight w/o options or variable weight = 880 lb
Unit base weight = 6,322 lb
GVWR = 8,800 lb
NCC = 2,478 lb

[Forrest]

You've done the math right and discovered that a 1/2 ton isn't up to towing a late model 30'. What you might do is go vintage. For instance, a 1966-1968 30' Sovereign has a unit base weight of about 4,750 or 1,572 lbs. less than the 2011 Flying Cloud. Even then you would need to pay strict attention to weight.

The other thing you might try is a higher rear end for your truck, such as a 4.11, and/or do one of Andy Thompson's tricks of going to a different tire size. In fact, if you're looking for magic, take your truck to him for modifications.

[SteveH]

Swissair,

Your numbers are right. You are getting into the same situation as most that want to tow a large Airstream with a 1/2 ton vehicle.

I do think the vehicle manufacturers are very conservative on the weight specs, but should you "do it"??????

There are some on here that say a 1/2 ton truck will tow any airstream built, but will it haul anything else? Will it do it safely? Will it do it long-haul without costly failures/repairs as a result?

[ROBERTSUNRUS]

Hi, your numbers are all theoretical, not actual weights. Actual weights might be better or might be worse. A magical hitch might add another 100 lbs or so to the equation. Other than that, if your tow vehicle doesn't make it, buy one that will for the trailer of your choice.

[ROBERT CROSS]

These Airstreamer's that think they know everything about towing really annoy those of us who do.

Just do it...you'll know if it's rite.

You'll probably keep the AS a lot longer that the Burb anyway.

After all.... you REALLY want that Airstream don't 'ya!

Bob

[dznf0g]

If it were me, I'd just lose the P metric tires, get wheels rated for LT tires and drive off. I've towed with an Avalanche with a 3.73 and 5.3 liter. Although it was anemic, it felt good as far as stability. I have also towed with a Denali XT 6.2 liter with a 3.73. It had plenty of oomph and braking was fine. I do downshift in the mountains to take some load off the brakes. The Denali was fine except for the "22s" and low profile tires. If it would've been mine I'd get rid of them and move on down the boulevard.

If you choose to use the Burb, (other than the tire and wheel recommendation) just pay closer attention to your maintenance items. I am sure with a 4.10 and 6 liter, it is a HD tow packaged vehicle. It might be prudent to install a trans temp gauge (unless you have the DIC with trans temp already there). Maybe an additional cooler if temps consistently run over 200* on the flats.

[SteveH]

When I checked in '08 about an '07 1/2 ton pickup (GMC), 4.10 gears were not available for the small rearend, which at that time at least, all the 1/2 tons had.

3.73 was the lowest gear set that GM made for that rearend.That's what the dealer told me.

[Streamside]

Originally Posted by swissair

If my math is right then my family of four will exceed the GVWR for my 1/2 ton suburban, even w/o including any cargo. After gathering all the numbers shown below, I take my GVWR of 7,400, subtract curb weight of 6,100 and tongue weight of 880 (30' Flying Cloud) leaving a max of 420 lb for combined people/cargo. That would mean no cargo and leaving one of the kiddos home alone. Wife said no on both counts. To make the numbers work on paper we'd be limited to a 23' Flying Cloud, but we want the 30 footer. So, here is my question for the pros - is there anything I'm doing wrong with the numbers?

If the math is good, then is there anything I can do to make this TV + AS marriage work? Will a high quality no-sway package combined with AS superior aerodynamics mitigate safety concerns? The AS dealer suggested that it would, but I'd like to hear from others. Here are the other numbers:

TOW VEHICLE
2007 Chevy Suburban 4WD, ½ ton, 6 liter V-8.
Rear axle ratio = 4.1
Curb weight = 6,100 lb
GVWR = 7,400 lb
GCWR = 14,000 lb
FAWR = 3,600 lb
RAWR = 4,200 lb
Owner’s manual says max trailer weight is 7,900 lb

HITCH
Class V-5.
Tongue weight carrying –600 lb
Tongue weight distribution – 1,000 lb
Trailer weight carrying – 5,000 lb
Trailer weight distribution – 10,000 lb

TIRES
Load index 108 (2,205 lb), but inside door panel says people and cargo should not exceed 1,304
Size – 20.5” x 8.5”

TRAILER
2011 Airstream 30’ Flying Cloud.
Hitch weight w/o options or variable weight = 880 lb
Unit base weight = 6,322 lb
GVWR = 8,800 lb
NCC = 2,478 lb

Save the real marriage, if you spend this much energy in analyzing....then you know the answer. I tow 31 ft with a 3/4ton truck and enjoy the drive. I also overkill with a pp hitch, E rated 16 tires, just so I don't worry about the important ones sitting next to me. That is what it is all about, no worries... If you have worries, take care of them.....

[Not Done]

For years I've heard poeple say the "only" difference between 1/2 and 3/4 is an extra leaf... I tend to think about silly little things like brakes and transmission coolers. Then again, on my F250 the auto parts store would always ask if mine had the 1/2 ton or 1 ton brakes.

Others have made good points, older trailers tend to weight less, how long do you plan to keep the suburban. I will point out that you don't have a lot of hills in TX.

[barts]

I would not do this.

If you would exceed only GVWR but you're within axle and tire weight ratings, I'd suggest that you fit some ride-rites and have fun. But...

Your rear axle weight rating will be exceeded.
Your rear tires will be overloaded.
Your gross vehicle weight rating will be exceeded.
Your gross combined vehicle weight rating will be exceeded.

This isn't the right way to do this.

My diesel F250 is happy pulling our vintage 25' trailer - but by the time I add four people and gear for Burning Man, say, we're a bit heavy too.
You need a lighter trailer, or a beefier tow vehicle.

- Bart

[Airperson]

My humble advice is buy the trailer you need and want. The Airstream will be with you through many tow vehicles. Over the coming years all the tow vehicles you have owned will be rusting by the roadside yet, your well maintained Airstream will be raring to go. I think you already know the answer to your question there aren’t any magic answers on the forum. We have a Ford 250 it will pull our trailer with ease and safely anywhere we care to go.

[Silver Otter]

All good advice from the vets above. May I add my experience as a new owner of a 30 ft? We started this spring with nearly the same set up as you describe. I never felt "unsafe" because the AS pulled well on the flat, the after market trailer brake worked well, and the Hensley kept her light and straight. All except we tried to pull up the hill.

By the time we knew we were going to the West Coast we *knew* we needed more truck. The difference between the old V8 gasser 1/2 ton and the used diesel 3/4 is night and day. Having done both, we will always have a 2500HD to pull our Silver Otter. Everything is better with the heft truck. Since last May we've pulled just over 20,000 miles, 26 states and one province. This is really Fun!

[swissair]

Thanks for all the replies. And, yes, the real marriage is paramount. Since I don't have the 30' yet, I can't take it to the scales to get actual numbers, but even if I could do that it sounds like we'd be cutting things close and I know we'll eventually want to bring more people and haul more toys. The vintage option sounds intriguing and I know the AS holds value as well as any out there. But, as this will be our first AS (or RV for that matter) I think we'll want the warranty and hopefully less maintenance issues as we learn the ropes. We're excited to get out there, but I know we'll feel better about it if the TV is not weight challenged. We love the suburban for its interior space and general use when not towing, and don't have much need (or additional garage space) for a pickup. So ... I think my next step will be to research just how much more capable a 3/4 Burb is for the money and maybe consider other TV options as well. Glad I posted!

[Andrew T]

If past history is any indicator I am thinking you are fine with the 30' and Suburban.

Over the years there have likely been at least 10,000 or more families that have towed large Airstream's extensively with 1/2 ton suburbans, I would think it is the most tested Airstream combination. In the 80's it was by far the most popular tow vehicle around. At an International rally there would be at least a couple of thousand in one place and though some had 3/4's most used 1/2 tons. In the 70's & 80's. 80% plus of new Airstream sales were 31 and 34's it is only in the last 10 years that we started to sell larger numbers of smaller trailers. The new Flying Cloud is pretty close to the same weight as an optioned out 70's model 31' which most of them were.

The 1/2 ton Suburban chassis uses the same components as the old 2500 light duty pickups so the axle is larger hence the availability of 4:10 gears.

You will be over your GVWR but should be able to stay within your GAWR ratings with a proper hitch set up. Many 3/4 ton diesel trucks are also over their GVWR just not over their GAWR's.

When you set up your torsion bars some of the hitch weight is transfered rearward to your trailer wheels so not all of the 800 lbs winds up being supported by the truck. That nice large storage area behind the rear seats will be tempting to fill with stuff but try and keep it to bulky light items. I have weighed numerous 1/2 ton Suburbans set up with large Airstreams and never found one way out on weights, usually the rear axle is around 4000 lbs. I have seen a couple in the 4400 range with Airstreams with higher hitch weights but even these were well below the tire capacity. Your brakes are huge compared with what we historically towed with and almost identical to the brakes on a 3/4 ton.

A couple of suggestions. If you have 17" tires LT 245/70R x 17" Load Range "D" tires will give you better handling, you can use these on your same rims with 50 PSi for towing and back them to 40 for solo use. If you do not have computer command ride control a good set of shocks such as Bilsteins will make a dramatic difference. Wtih these to changes the handling is actually more stable than a 3/4 ton in most real world situations.

You should strengthen or replace your hitch receiver as the factory one on its own will not properly transfer weight. Make sure the weight distribution system allows the ball to stay in as close as possible to the back of the Suburban and that the torsion bars have a tapered design to allow the hitch to travel through dips etc.

I hope this helps.

Andrew T