Early 70's tow suburban
 

I have a mid 70's Airstream and I would really like to find an early 70's Suburban to tow it with. What all needs to be done to make these old suburbans good tow vehicles? I currently use my 99 Burb for daily and tow driving and wouldn't mind a vintage 70's to replace it. I am thinking I would want to update the seats with headrests for some safety reasons, but I really want to know what needs to be done to prepare it to tow a camper safely. I would want disc brakes on at least the front (like my curent one), any suspension things to do? Can newer truck parts bolt on to the older ones to fix any of the issues? Things like brakes, suspension, steering,...? Any input would be great, or a ready to go one would be even better. :)

Re: Early 70's tow suburban
 

This question is bound to get a lot of discussion from each group of Suburban fans out there.

So I will start with my overly biased opinion just to make this easy :)

These are the basic things I would want.

1. 3/4 ton
2. Leaf spring suspension
3. Air bag over loads
4. Low gears 4.10 is a good all around ratio
5. Updated rear brakes.
6. Full floating axles
7. Manual transmission
8. Engine set up for low end torque
9. Heavy duty engine cooling system
10. Class 3 or 4 hitch, set up for torsion bar system.

There are many ways to achieve the above, it all just depends on the direction you want to take your Suburban build.

Stock?
Modernized?

Stock:
Personally I would just save all the hassle of a build up and just find yourself a K20 Suburban, since it will have all the beef in the chassis you will ever need right off the bat.

Modernized:
The sky is the limit, depending on your bank account. Lets just say you have no issue with funds, and are not in any kind of hurry. Start by finding the most solid and complete Suburban you can afford, doesn't matter what it was optioned with from the factory since you will replace it all anyway. The goal is to find one that has the best overall quality in the body work, and the complete interior in ready to live with condition.
Drive train.. You could find a rolled over new Chevy/GMC truck, buy it whole and then swap the drive train into the old Suburban. Or, you could just buy each piece new from GM or from a quality shop.
Suspension.. If you are not interested in 4x4, then you can put in a whole new air ride suspension. If you are interested in the 4x4 route, then it's a cheaper and easier route IMO.

The list of ideas and suggestions can go on and on, but first we need to know what your desired end result should be and what kind of money/time you are willing to spend.

Re: Early 70's tow suburban
 

Years ago, I towed frequently with my 72 (coil sprung). Even with trailer brakes I was, at times, wanting more. Other than that, it did great. There is more room inside than newer Suburbans.

Re: Early 70's tow suburban
 

I have towed regularly with my 68 and it handles a trailer just fine, but I've got a little more torque under the hood now. I would recommend a leaf sprung truck (even if a 2wd) as it seems a little more stable and handle a load better than coils.

As far as newer axles, most can be fit in place with a little welding for new spring pads. I run a 2005 GM 11.5 AAM rear axle in my 68 (with factory discs/parking brake) as well as a front Dana 60 from a 1991 Dodge W250 (engine donor as well). Slightly overkill for a tow rig, but it goes to show that axles can be swapped around. If you're thinking 2wd, the stock front suspension would be fine, probably add a sway bar and a basic rebuild (bushings, bearings, etc). The design was used for nearly 3 decades (thru 87/91) and can handle a load just fine.

And I agree with what Chris posted above, and get the best body you can afford, everything else can be swapped around but body work isn't cheap nor easy. Heck, pick up a wrecked Suburban of a similar year to your current one and toss the drivetrain and seats into an older body.

Re: Early 70's tow suburban
 

did you see this one ? It's cheaper to ship compared to hiring out body work.

http://kpr.craigslist.org/cto/4443691247.html

Re: Early 70's tow suburban
 

Thanks! I have emailed about that one.

Re: Early 70's tow suburban
 

What's the weight on that airstream? You may not need to do much at all depending on the trailer weight.

My wife and I are thinking about an old airstream. I'd like to see some pics, either here or on another thread (as you deem appropriate).

Thanks, -

K

Re: Early 70's tow suburban
 

Our Airstream weighs about 3500 pounds. We do not load it down a lot and do not travel with full water/waste tanks. Travel weight is probably about 3800. You can see some photos of the interior of our camper at http://cmsmithportraits.com/blog/?p=24249 and at the bottom of the blog page you can type in Airstream in the search box to find more photos of it. We love it and it has been a great addition to our family! Strongly recommend it, but also know that owning an Airstream is unique in the camping world. There is almost ALWAYS something new to do to it on every trip and they are not the best layouts compared to the newer campers. But I would not have it any other way, personally!

Re: Early 70's tow suburban
 

This Suburban is used for towing all the time, open trailers with new projects and a travel trailer:

http://www.67-72chevytrucks.com/vboa...d.php?t=625017

Re: Early 70's tow suburban
 

Ah - 3800 lbs - you could tow that with a Yugo!

(lol)

Seriously, though: I have routinely towed an open trailer at about 4600 lbs with a 1/2 ton pickup (four drum surge brakes on the trailer) for about 45 years.

I don't think you'll have any trouble with a vintage Suburban pulling 3800 lbs.

I'll check out your Airstream photos. Let me know if you see one (needing work) for sale - we can travel to pick it up!

K

Re: Early 70's tow suburban
 

Try owning a racecar... :waah:

:lol:

Re: Early 70's tow suburban
 

Here Keith, a little inspiration for you...

I grew up with this camping rig. My grandpa, before he passed, gave my dad his 1975 31' Airstream and 1988 R20 Suburban.

We still have the trailer, but sold the Suburban a year ago. It had a TBI 454 and TH400 in it. Cruise, A/C, P/S, P/B, tilt, power locks, manual windows. 98,000 original miles when we sold it.

Re: Early 70's tow suburban
 

I agree with Keith. With a trailer that light, an old Suburban will tow no problem. With ours on the other hand, a 31' trailer needs something big to pull it.
That 454 had the power to pull it, but you could almost see the gas gauge drop. It just was too expensive to pull very far.

For your trailer, I think you'd be just fine with a 1/2 or 3/4 ton Burb. A 350 should pull it no problem.

I can recall looking in an old magazine from 1973 a few years back. In it was an add for a 1973 Suburban, pulling an Airstream.

Obviously, this decision really depends on what body style you want for your Suburban. Keep in mind though, Suburbans from before 1973 have only 3 doors originally. If you'd rather have 4-door, you'd need a '73 and up.

Re: Early 70's tow suburban
 

IMHO, for the trailer you describe any 3/4 ton Suburban or a 1/2 ton with helper springs should be more than adequate. My '67 C10 (327 4-speed with factory heavy duty springs, shocks, overload springs, etc.) has pulled a 2,000 lb. trailer with 2,800-3,300 lb. Corvettes on it all over the country without incident. Even a stock 327/350 should have enough umpf to tow it comfortably unless you're in steep terrain. 4-wheel drum brakes will require a change in driving habits or heavy reliance on trailer brakes, but I think the later 'Burbs ('71-72?) had disc front brakes from the factory (double check that with more knowledgeable members :D ) and I believe it's any easy conversion for earlier ones. A stick shift is the most durable and lowest maintenance transmission for towing, but a healthy TH400 shouldn't give you any trouble for a long time.

Happy shopping! I hope to own a small Airstream to tow behind my 'Burb some day. As others have mentioned, GM used Airstreams behind Suburbans in a lot of sales literature.

Re: Early 70's tow suburban
 

Thank you; pretty trailer. I may need some tips on keeping the thing polished up if we find one...

K

Re: Early 70's tow suburban
 

Do you think that the airbags are needed? I use a ProPride hitch on my '99 and would plan to use it for a "new" tow vehicle as well. I found a c20 in good shape not far from me that I want to go take a look at. Would the c20 need the extra support of the bags or are those more for lowering it?

Re: Early 70's tow suburban
 

Also, those of you that use them for travel, have you put in newer seats with headrests and seat belts mounted to the seats? What fits best, looks good, and helps with the head safety the most?

Re: Early 70's tow suburban
 

Man thats a nice trailer.

On towing weight, I have on on a few occasions towed my old Civic on my open car trailer, the combo together weighted about 4300lbs, more than your camper and it was like nothing to my stock C10. So as long as the Suburban is well maintained it shouldn't have an issue towing your Airstream. I plan on getting a vintage Airstream to tow behind my Oldsmobile at some point, the car is rated for 5k with just a Class 3 hitch.

Re: Early 70's tow suburban
 

I towed all across the east coast with mine. Camper weighed in at 7,300 lbs... but she wasn't exactly "stock" :metal: It sat on a '99 3/4 ton Suburban chassis with a Fuel Injected Vortec and a 4L80E. Towed the camper the A LOT.

For seats, I went with '05 Burb leather seats. Seatbelts are mounted in the seats, much safer with the 3 point seatbelts. Bolt right in.

Stupid economy... (business got tight... had to sell it)

http://i213.photobucket.com/albums/c...b/IMG_7846.jpg

http://i213.photobucket.com/albums/c...b/0498541a.jpg

http://i213.photobucket.com/albums/c...10607-1419.jpg

Re: Early 70's tow suburban
 

How was the process of combing the old with the new? I wondered about that as an option.

Re: Early 70's tow suburban
 

i would put a modern drive train into an old suburban and beef up the suspension and call it a day.

Re: Early 70's tow suburban
 

:agree: It involves shortening chassis 5-6" and all the associated parts, plus new body mounts, etc... Not worth the hassle. Fortunately, I bought it as an unfinished project after all the hard work was done. Just get a stout engine/tranny combo with a good cooling system (engine and tranny). And beef up the brakes, suspension and steering components. If I were to do it again, I would keep it simple.

Re: Early 70's tow suburban
 

Absolutely not. You can easily put in a LSX with 4l80e into the original frame.

I'm not taking about transplanting body on modern chassis

Re: Early 70's tow suburban
 

If you have a Pro Pride hitch your in great shape already. Id get a set of Air Lift or Firestone helper bags to mount inside the rear coils. Currently neither company iirc has a part number listed for a 67-72 c10 though. So you will have to measure the inside id and height of the springs while installed on the vehicle and they will find a bag close enough to fit.
I would also rebuild both front and rear suspensions and add sway bars on both ends. These make a dramatic improvement in handling when not towing as well.
3.73's are also a good choice but I would not rule out 3.07's if you have a big inch SB or BB.
TH400 is a great HD auto tranny just add a extra tranny cooler and your good to go. Of course a 4 speed would be better for towing I personally prefer an auto.
Last dont skimp on the cooling system! ID buy the biggest 2 or 3 row aluminum radiator I could get. You might also consider adding an auxillery electric fan as well. A bottle of water wetter is also good practice.
With those mods and your Pro Pride you wont have a bit of trouble towing with a coil sprung 'Burb.

Re: Early 70's tow suburban
 

IMHO, if it's a half-ton with shorter (29-30") tires then 3.73's are about the best gear ratio unless you have a big block, or something of equivalent output, to pull you along in spite of a faster ratio. If it's a 3/4 ton with 16" wheels (and most likely 31-32" tires) then 3.73's will still be good but 4.10's will give it a lot more grunt on hills - as long as you don't expect to drive over about 65MPH for extended periods. I think a lot of owners feel like their rigs are "wound out" at anything over 60 with 4.10's, but as long as the tire is at least 31" or so high a stock engine will be right in its power curve at 60-65. Also, within a reasonable range of tire/gear combos I honestly don't think it makes as much difference in fuel economy as you'd think - the best thing to keep it mind is that GM engineered these babies to pull, and to expect to improve their drive train combinations much without an end-to-end conversion to more modern components is a vain effort.

Re: Early 70's tow suburban
 

Thanks for the info, everyone. It is something I really want to do, but I need to consider all factors of an older tow vehicle. It would look great (but need work to look that way most likely), should have plenty of power that could also be updated if I want, and I would need to put money into it considering safety both in handling and simple things like head rests and seat belts. This all gives me plenty to think about.

Re: Early 70's tow suburban
 

So is there any extra concern for safety? Upgrading the suspension, brakes, maybe interior seats will do a lot, but is there concern for the additional upgrades that can never be retrofitted? I REALLY want to go with a vintage tow vehicle, but I have some struggles with it and my family riding in it.

Re: Early 70's tow suburban
 

With out doing a chassis swap from a newer truck, so that you can get the modern brakes and suspension.

The thing I would focus on the most is the brakes.
If you go 3/4ton, you can upgrade to a 14 bolt full floating axle. These axles have giant drum brakes on them.
For the front brakes, if two wheel drive you could upgrade the size of the discs and new calipers. But you may run into issues with wheel diameter if you want to keep the stock looking steel wheels.

Interior wise, you can install shoulder harness seat belt on all three benches. Minus the seating position next to the 3rd door.

Old cars/trucks don't have all of the modern safety as a new vehicle, since they are running what was considered safe designs of the time. Retrofitting modern safety equipment into a classic is a whole costly project in itself.

I know in my 1968 Suburban, I only drive it at 1968 performance today. Meaning I do not travel faster than 65 MPH, and I keep a very large buffer between me and other cars.

Re: Early 70's tow suburban
 

How funny, was just telling my wife we need to find a vintage Airstream to tow behind the Suburban :-) I echo Chris' prerequisite list for towing:

1. 3/4 ton
2. Leaf spring suspension
3. Air bag over loads
4. Low gears 4.10 is a good all around ratio
5. Updated rear brakes.
6. Full floating axles
7. Manual transmission
8. Engine set up for low end torque
9. Heavy duty engine cooling system
10. Class 3 or 4 hitch, set up for torsion bar system.

I would also add a nice Tekonsha Electronic Brake Control.

We have a couple horses and normally use our 7.3 Diesel Excursion to pull them but I would not hesitate hooking up the Burb (after I upgrade to a Class 3 or 4 hitch and get a larger gas tank!) The 454 in our burb has plenty of low end torque but goes through 12-15 gallons every 100 miles!
Brian

Re: Early 70's tow suburban
 

"Extra" concern for safety? It depends on how far you want to take the question. Do these vehicles have crumple zones built into the body, side air bags, etc.? Obviously, no. If you want to safely (subjective use of the word) tow your camper and exercise the driving habits of most other people on the road today, then it will require extensive modification of an older Suburban or forgetting about a classic tow vehicle altogether to accomplish it. However, if you can adjust to always leaving extra room in front of the vehicle while moving, knocking 5-10 MPH off your cruising speed (depending on how fast you'd tow with a new vehicle), and understanding what the vehicle's limitations are - which aren't as far from modern trucks as a lot of people think - a classic 'Burb will serve you well in close-to-stock form. And above all, no matter what you're driving, your family's safety depends on your attention and judgment.

Re: Early 70's tow suburban
 

I have a question. Would a 70 Suburban with a 1 ton rear end with 4.10 gears, a 350 with a sm465 tow an 8000lb trailer? Looking at travel trailers and can't really find much info on the web. Thanks.

Re: Early 70's tow suburban
 

Back in the day my dad towed his 1975 vintage 5th wheel with his 73 4x4 F250. It had the 300 six (about 120hp). It would go 58 mph flat out on level ground and dropped to about 45 in 3rd gear on any real hill. He was a logger in northern Idaho and drug that trailer around for years that way. Your stock 350 will be able to better his performance, but you will most likely have difficulties staying at the speed limit on the larger uphill grades. A lot of the "will it tow it" debate has to do with what you are expecting and are willing to put up with. Today we have a large selection of brake system upgrades and trailer brake controllers are way more advanced than back then. Not knowing what tire height your running I can't speak to your ability to cruise at 75 on the interstate, but an overdrive would be a nice addition both for fuel and driveability. With the right additions your Suburban will do a great job towing. Just my two cents worth. Your results may vary.

Re: Early 70's tow suburban
 

Thank you for your thoughts. I have 33" tires. I know a weak link will be the drum brakes but if/when needed, I could change the fronts out. I'm not concerned with going any faster than posted speed limit. I don't do that now come to think of it. Is there any difference in the frame "beefiness" between series of Suburbans that old?

Re: Early 70's tow suburban
 

Years ago, just for laughs, I measured the frame thickness on my 3/4 ton and another 1/2 ton. I seem to remember the difference was only .010".

Also the frames changed very little up to the 1992 model year when GMT400 style came out.

Re: Early 70's tow suburban
 

Is it a 3/4 ton chassis? For pulling a trailer weighing 8K on long trips, a small block will have to be specifically built for the purpose to hold good speeds without being wide open on any hill. Strictly speaking on the figure of 8,000 weight and the assumption that it'll be over long distances, in terms of near-stock equipment available on our trucks I'd want a big block and good 3/4 ton running gear and stout rear springs or air bags. 4.10's are good general-purpose towing gears when an overdrive transmission or extra tall tires aren't present. Your SM465/4.10/33" tire combo is one of the better ones for towing that much weight at highway speeds (55-65 MPH), but it's a strong 350 or 383 that will move that much weight with much gusto. Disc front brakes are a good idea, as well as trailer brakes unless you have very large (i.e., 1-ton) brakes on the truck. Only one of the trailers I've had hooked up to my '85 C3500 had brakes and I've felt comfortable up to around 9,000 lb. total payload, but those are the big Bendix slide-type front calipers, 13x3.5? rear drums, and hydroboost assist. I'm hesitant to hook up to more than about 3K with my 'Burb's 4-wheel drums in the shape they're in right now. :O

Re: Early 70's tow suburban
 

From what I have been able gleen from the 1967 truck manual the basic frame on all of the C/K series 10/20/30 are the same, but the factory would rivet various pieces of formed angle iron to the frame to stiffen it up depending on the application. The manual I have doesn't show them but explains the basic ideas with some simple drawings in the frame section. Then it gives a "section modulus" number in the standard equipment listings for comparison. This information may only be in the 1967 manual as it is the first year in the model (common GM practice). It also refers to a frame chart but I have been unable to locate that chart. Hope this helps.

Re: Early 70's tow suburban
 

Thanks guys.

Hey Alex, I wound be towing this trailer too much. It's going to be a permanent home for me and my boy. I doubt it'll even get out of Oregon for some years to come. I just want to be safe and others to be safe when I'm pulling it.

Re: Early 70's tow suburban
 

Oh! If it's just moving one-way occasionally, a good 4 bbl. 350 will pull it and other areas of the truck should be of more priority. Maybe not fast, but it'll get the job done and be more practical every other day of the year.

Re: Early 70's tow suburban
 

8k pounds is ALOT of travel trailer. Is that empty? Figure at least another 1000 pounds when loaded, and thats conservative.
I wouldnt be as concerned about the power as much as the suspension and handeling. Although it will be a slug, just sayin.
How much tongue weight? What kind of WD hitch do you have in mind?
Travel trailers are about the most sway prone trailers. Better consider a Reese Dual Cam or equivalent.
Do you currently have 8 or 10 ply tires? You will be adding weight to the back as well as the front with a WD hitch.
Not trying to disuade you, just passing along lessons i've learned towing a 6k pound trailer. Good luck!

Re: Early 70's tow suburban
 

It's a 7k lb trailer dry actually. Not sure about the WD hitch type but will definitely be getting one. I know it's a ton of weight and was actually thinking of a 5k trailer, but they're all kinda small for full time purposes. Weekend trips they'd be perfect. Thanks for your honesty fella.