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Flat towing suburban [message #290270] Thu, 12 November 2015 15:44 Go to next message
skip2 is currently offline  skip2   United States
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Yes I have asked about this before. Let me say right up front that I agree a Suburban is twice as much as should be flat towed. But the CFO can't understand why some will tow an enclosed trailer with a vehicle in it or a flat bed with a vehicle on it and got to be at 3 ton. I know some of you guys with the proverbial engineering degree know the reason you can pull a heavy trailer with the axles closer and further back as opposed to pulling a vehicle with all 4 down. The PO used to do it with mine and I know of several others. Inquiring minds want to know. I do have a brake buddy and 3.21 final drive if that means anything. I've towed a 3000lb mustang with no issues but it got procured by immediate family. Just trying to come up with an answer other than "because they say it shouldn't be done"
Skip Hartline


74 Canyon Lands, FiTech, 3.7 FD LSD, Manny Tranny, Springfield Distributor, 2001 Chevy Tracker Ragtop Towd
Re: Flat towing suburban [message #290272 is a reply to message #290270] Thu, 12 November 2015 16:00 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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I would hate to see the gas mileage hauling a suburban around... I thought of flat towing my old 85 grand wagoneer, but then I knew how much more into the accelerator I was with just 3000 pounds of trailer on behind, and how much is slowed up on hills. I decided to try to find the lightest tow vehicle I could find, just for that reason.

I would guess the suburban to be over 5000, yet should under 6000 pounds if you put it on a scale. some might claim that the suburban might push the coach around too much, but I would think with the brake buddy, and if the burb is in good repair, it should be fine. I have driven some older suburbans, that I would not want to tow, just because the ball joints, ectt.. were bad, and it was work keeping it going straight when driving it.





Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: Flat towing suburban [message #290275 is a reply to message #290270] Thu, 12 November 2015 17:03 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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Registered: April 2011
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skip2 wrote on Thu, 12 November 2015 15:44
Yes I have asked about this before. Let me say right up front that I agree a Suburban is twice as much as should be flat towed. But the CFO can't understand why some will tow an enclosed trailer with a vehicle in it or a flat bed with a vehicle on it and got to be at 3 ton. I know some of you guys with the proverbial engineering degree know the reason you can pull a heavy trailer with the axles closer and further back as opposed to pulling a vehicle with all 4 down. The PO used to do it with mine and I know of several others. Inquiring minds want to know. I do have a brake buddy and 3.21 final drive if that means anything. I've towed a 3000lb mustang with no issues but it got procured by immediate family. Just trying to come up with an answer other than "because they say it shouldn't be done"
Skip Hartline
Some vehicles route air better than others, so weight is only one factor in gas mileage.

As far as weight is concerned, consider that the drivetrain was designed for a vehicle of less than 2 tons curb weight, and loaded without a towed you are using that same drivetrain to drag 6 tons.

Now, how much towed do you want to add to that?
Re: Flat towing suburban [message #290276 is a reply to message #290270] Thu, 12 November 2015 17:18 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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That is a lot of weight to tow but it is most likely easier to tow 3 tons around flat Florida terrain then 1 1/2 tons of normal toad in the mountains..

Roy Keen Minden,NV 76 X Glenbrook
Re: Flat towing suburban [message #290280 is a reply to message #290270] Thu, 12 November 2015 19:06 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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skip2 wrote on Thu, 12 November 2015 16:44
Yes I have asked about this before. Let me say right up front that I agree a Suburban is twice as much as should be flat towed. But the CFO can't understand why some will tow an enclosed trailer with a vehicle in it or a flat bed with a vehicle on it and got to be at 3 ton. I know some of you guys with the proverbial engineering degree know the reason you can pull a heavy trailer with the axles closer and further back as opposed to pulling a vehicle with all 4 down. The PO used to do it with mine and I know of several others. Inquiring minds want to know. I do have a brake buddy and 3.21 final drive if that means anything. I've towed a 3000lb mustang with no issues but it got procured by immediate family. Just trying to come up with an answer other than "because they say it shouldn't be done"
Skip Hartline


Skip,

There are some very simple issues here.
Towing a heavy load will only shorten the life of the drivetrain manufactures worry about this for warranty. It isn't likely to kill you.
The two real problems are stopping the with the load and handling issues caused by the load. Either of these can kill you.
Most towing problems are caused directly by the nut behind the wheel. The mere fact that you can keep a GMC roadworthy means you are capable of firing synapses in the correct order. This is not as common as it should be. (Darwin was an optimist.)
I used to have the papers for establishing towing limits for both Ford and GM. That does not matter as much any more as SAE has finally written this and I never have had that one.

The real problem with towing with a TZE can be addressed easily. Get a higher numerical final drive (higher even than 3.21), you have a Brake Buddy. Now just get good tow gear and maybe a transmission temperature gauge.

What the vehicle and drivetrain was designed for is never the limit.

Matt




Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Flat towing suburban [message #290282 is a reply to message #290270] Thu, 12 November 2015 19:19 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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What year Suburban? Does the transfer case have a true neutral setting? My Tahoe does not (1997)

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Flat towing suburban [message #290284 is a reply to message #290270] Fri, 13 November 2015 01:20 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Registered: January 2004
Location: Hebron, Indiana
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Just something to think about

In flatlland country the weight of what you are towing is not very important.

I regularly tow a 11,000 GVW trailer with my John Deere diesel tractor on it. In fact I am towing it tomorrow evening. I use my 5 cylinder Colorado for a tow vehicle. It moves and stops it with it with ease. The total weight of the trailer and tractor is a little over 9500 pounds. I only take abut a 3 mpg hit from 21 to about 18 towing it.

What does matter is the wind resistance of the load. That tractor and flat bed trailer have a very low resistance. I have towed my nephews single axle box trailer and it is a hand full. My mpg drops to 12 or 13. The trailer and load weight is less than 1/2 of my 4 wheel flat bed with the John Deere on it.

On the discussion of Suburban weight. To give you a comparison, I ran my much smaller S-10 Blazer across an Indiana state weight station scale on the Interstate this spring. It weighed 4860 pounds with 1/2 tank of fuel and only me inside.

If you want to know what a vehicle weighs, in most states they leave the scales turned on when the weigh station is closed. So just pull in to a closed station and read the display on the driver's side next to the weighting platform to see what you weigh.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Flat towing suburban [message #290286 is a reply to message #290282] Fri, 13 November 2015 06:43 Go to previous messageGo to next message
skip2 is currently offline  skip2   United States
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Forgot to mention it is a 2000, which all the charts and owners manual say just put the transfer case in neutral
Skip


74 Canyon Lands, FiTech, 3.7 FD LSD, Manny Tranny, Springfield Distributor, 2001 Chevy Tracker Ragtop Towd
Re: Flat towing suburban [message #290298 is a reply to message #290286] Fri, 13 November 2015 14:45 Go to previous messageGo to next message
George B. is currently offline  George B.   United States
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From a mechanical standpoint you can get buy following the others recommendations. However, from a legal and/or insurance standpoint exceeding the owners manual limits could get you in trouble should you have an accident.
Quote from the owners manual:

"The maximum loaded trailer weight which you can pull with your vehicle depends on what special equipment has been installed.
GMC does not recommend towing any trailer OVER 1,000 POUNDS GROSS TRAILER WEIGHT."

That small limit puts us all at risk.


George Butts Las Vegas Nevada 73 "Custom 26' Q" & 76 23' Birchaven 71 Honda 600 Coupe & 01 Tracker Toads
Re: Flat towing suburban [message #290301 is a reply to message #290270] Fri, 13 November 2015 15:49 Go to previous message
skip2 is currently offline  skip2   United States
Messages: 544
Registered: September 2011
Location: Winter Haven,FL (center o...
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I completely understand it's twice the strain on the GMC but is there something with the axle placement as opposed to a trailer's axle placement that could make it do funky things with the handling other the the given that would happen when taking emergency avoidance maneuvers would bring up. I don't plan on trying to pull it, my tranny has been to dependable. Just got curious about the physics involved from someone saying it would want to control the tow vehicle since it is at least half the weight of the GMC. Thanks for all the responses.
Skip Hartline


74 Canyon Lands, FiTech, 3.7 FD LSD, Manny Tranny, Springfield Distributor, 2001 Chevy Tracker Ragtop Towd
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