Tahoe vs Suburban

wnjj wrote:

JBarca wrote:
Hi Guys,

I used to have a 2002 K1500 Tahoe and replaced it with a 2003 K2500 Suburban. Both where good trucks, the Burb even had rear wheel steering (Quadrasteer). I sure miss that truck, we just grew out of the towing capacity. I have measured both and here is the differences concerning wheel base and rear overhang.

If I put my Reese HP WD shank in the truck receiver I had this:

2002 K1500 Tahoe:
- 116" wheelbase
- 58" rear overhang (rear axle to tow ball)

2003 K2500 Suburban:
- 130" wheelbase
- 65" rear overhang

One would think the shorter rear overhang would give the Tahoe an advantage, however the math says no.

A rule of thumb for towing stability is the rear overhang is no more than 1/2 the wheelbase. So lets see.

Tahoe: 116/58 = 2 Or the rear overhang is exactly half the WB

Suburban: 130/65 = 2 Or the rear overhang is exactly half the WB

so the ratio of rear overhang to WB is the same.

Now lets look at the force moments if we apply a 500# side load agasint the tow ball. What is the force of resistance at the front axle?

(Summating forces around the rear axle)

Tahoe: 500# x 58" = Y# x 116" Solving for Y, 250# seen at the front axle.

Suburban: 500# x 65" = Y# x 130" Solving for Y, 250# seen at the front axle.

According to the math, as far as WB and rear overhang there is no difference in stability between the Hoe and the Burb.

If the Burb with 130" WB had a 58" rear overhang, it would be better.

From what I have found, tire sidewalls flex will have a significant effect on towing stability, even in the 2500 Burb. Been there and felt/proved that. The wrong tires, LT E load range or not can make or break the stability of a tow rig. It was more of a factor then the rear overhang concern in this case.

Hope this helps

John

I completely agree with your data and calculations, well done, I respectfully disagree with your conclusion of them having the same stability. When the front tires sees those 250 lbs of side load, the sidewalls act a bit like springs and deflect. Given that both vehicles deflect the same amount sideways at both the front and rear wheels, the longer wheelbase one will be traveling closer to its original course than the shorter one. That is more stable in my book. I calculated over a 14% difference in angle of travel between the two using 1/2" of lateral movement at rear and 1" at the front. ( angle = arctan(1.5 / wheelbase) ). For a simple demonstration, set a ruler and a yardstick down and then move one end of each of them sideways by an inch. That smaller one will be pointing more sideways. While the difference is more subtle with the vehicles, it's still real.

This sideways yaw angle is one of the things that stiffer sidewalls help to minimize, regardless of the vehicle.

Hi wnjj,

H'mm good point. I did not think of that. Thank you for pointing that out. I was more after the leverage effect and missed the displacement at the front axle.

Now seeing this, I agree with you. If the rear overhang to WB ratio is the same, then the longer WB does have an advantage due to the displacement at the front axle will be less due to less angle. This will even be higher stability if the longer wheelbase, shorter rear overhang is in your favor.

While I can see the less angle being better, how much angle less it takes to gain a notable level of higher stability is another good question. It is for sure part of the equation.

When we bought our smaller camper we had the Tahoe. After becoming more educated I realized the rear axle in the 1500 was going to be in trouble when I fully loaded the camper and even before I reached that point. I still remember the feeling in the 2500 Burb the day I put the camper on the back of the truck and drove down the driveway. There was a global shift in left to right stability in the truck from the increased capacity of the 2500 rear suspension. You can fell it being more solid and less truck roll even at 10mph.

Then we bought our bigger camper we have now and we used the 2500 Burb on this camper now again only partly loaded it until I reached a 1,200# tongue weight and what gear I could in the camper until I came almost on top of the CGWR of the Burb. 15,750# GCW to a 16,000# GCWR. We used it this way for about 4 months until the F350 came.

Then the same thing, the day I put this camper on the back of the F350 driving down the same driveway, I felt that same global shift in stability. The F350 is 156.7" WB compared to the 130" of the Burb and both with 65" rear overhang however the truck suspension plays a role in rig stability too. Out on the open road at speed, then the longer wheel base helps combined with the more stable truck suspension.

When a wind gust hits the side of the camper, that force pushes on the towball and it pushes/starts to roll the truck suspension and the tires.

- Tire side wall stiffness
- TV WB
- TV rear overhang
- TV suspension/capacity stiffness
- TT length
- TT TW per GVW
- TT running gear/suspension

All of those factors are parts of the towing stability equation. Best is to get "all" of them as optimal as you can.

Thanks again

John

JBarca wrote:
Hi Guys,

I used to have a 2002 K1500 Tahoe and replaced it with a 2003 K2500 Suburban. Both where good trucks, the Burb even had rear wheel steering (Quadrasteer). I sure miss that truck, we just grew out of the towing capacity. I have measured both and here is the differences concerning wheel base and rear overhang.

If I put my Reese HP WD shank in the truck receiver I had this:

2002 K1500 Tahoe:
- 116" wheelbase
- 58" rear overhang (rear axle to tow ball)

2003 K2500 Suburban:
- 130" wheelbase
- 65" rear overhang

One would think the shorter rear overhang would give the Tahoe an advantage, however the math says no.

A rule of thumb for towing stability is the rear overhang is no more than 1/2 the wheelbase. So lets see.

Tahoe: 116/58 = 2 Or the rear overhang is exactly half the WB

Suburban: 130/65 = 2 Or the rear overhang is exactly half the WB

so the ratio of rear overhang to WB is the same.

Now lets look at the force moments if we apply a 500# side load agasint the tow ball. What is the force of resistance at the front axle?

(Summating forces around the rear axle)

Tahoe: 500# x 58" = Y# x 116" Solving for Y, 250# seen at the front axle.

Suburban: 500# x 65" = Y# x 130" Solving for Y, 250# seen at the front axle.

According to the math, as far as WB and rear overhang there is no difference in stability between the Hoe and the Burb.

If the Burb with 130" WB had a 58" rear overhang, it would be better.

From what I have found, tire sidewalls flex will have a significant effect on towing stability, even in the 2500 Burb. Been there and felt/proved that. The wrong tires, LT E load range or not can make or break the stability of a tow rig. It was more of a factor then the rear overhang concern in this case.

Hope this helps

John

I completely agree with your data and calculations, well done, I respectfully disagree with your conclusion of them having the same stability. When the front tires sees those 250 lbs of side load, the sidewalls act a bit like springs and deflect. Given that both vehicles deflect the same amount sideways at both the front and rear wheels, the longer wheelbase one will be traveling closer to its original course than the shorter one. That is more stable in my book. I calculated over a 14% difference in angle of travel between the two using 1/2" of lateral movement at rear and 1" at the front. ( angle = arctan(1.5 / wheelbase) ). For a simple demonstration, set a ruler and a yardstick down and then move one end of each of them sideways by an inch. That smaller one will be pointing more sideways. While the difference is more subtle with the vehicles, it's still real.

This sideways yaw angle is one of the things that stiffer sidewalls help to minimize, regardless of the vehicle.

I think JBarca has it calculated fairly well for forces and the comparison there.

Tires do make a world of difference. Take my wagon for instance. From 2008-2013, it was my tow vehicle. 26' 5,600 lb trailer.

Car has aftermarket Hotchkis sway bars, front and rear.
I've never towed with my winter tires, but they are the original 225/75R15 sized tires. Handles pretty bad with them.
Summer tires for the first several years were 245/60R17 Michelin Energy LX4 tires, an OEM style all season tire. They were an extra load tire with more load capacity. Handled pretty good with those tires. Towed fairly well with those as well but still had stability issues on really windy days. Ran those from 2007-2010 during the warmer months.
2011 I bought some 235/65VR17 high performance summer tires for it. Bridgestone Dueler H/P Sport XL tires made for high performance SUV's. Made a huge difference in towing performance. Much more stable, could pretty much run 65 mph in nearly all conditions with good stability.

116" wheelbase, same as a Tahoe.
219" overall length. (Tahoe 197", Suburban 219")

The rear overhang is HUGE.

Only switching from a single friction to a Reese Dual Cam sway control made more difference in the stability. Tires had a huge impact.

Hi Guys,

I used to have a 2002 K1500 Tahoe and replaced it with a 2003 K2500 Suburban. Both where good trucks, the Burb even had rear wheel steering (Quadrasteer). I sure miss that truck, we just grew out of the towing capacity. I have measured both and here is the differences concerning wheel base and rear overhang.

If I put my Reese HP WD shank in the truck receiver I had this:

2002 K1500 Tahoe:
- 116" wheelbase
- 58" rear overhang (rear axle to tow ball)

2003 K2500 Suburban:
- 130" wheelbase
- 65" rear overhang

One would think the shorter rear overhang would give the Tahoe an advantage, however the math says no.

A rule of thumb for towing stability is the rear overhang is no more than 1/2 the wheelbase. So lets see.

Tahoe: 116/58 = 2 Or the rear overhang is exactly half the WB

Suburban: 130/65 = 2 Or the rear overhang is exactly half the WB

so the ratio of rear overhang to WB is the same.

Now lets look at the force moments if we apply a 500# side load agasint the tow ball. What is the force of resistance at the front axle?

(Summating forces around the rear axle)

Tahoe: 500# x 58" = Y# x 116" Solving for Y, 250# seen at the front axle.

Suburban: 500# x 65" = Y# x 130" Solving for Y, 250# seen at the front axle.

According to the math, as far as WB and rear overhang there is no difference in stability between the Hoe and the Burb.

If the Burb with 130" WB had a 58" rear overhang, it would be better.

From what I have found, tire sidewalls flex will have a significant effect on towing stability, even in the 2500 Burb. Been there and felt/proved that. The wrong tires, LT E load range or not can make or break the stability of a tow rig. It was more of a factor then the rear overhang concern in this case.

Hope this helps

John

ktosv wrote:

wnjj wrote:
The longer wheelbase has an advantage even with the same overhang ratio. Suppose the hitch ball is suddenly pulled sideways 1 inch. With the same ratio on both vehicles the front will try to slide over the same amount on both vehicles to compensate BUT the longer wheelbase one will result in a smaller yaw ANGLE which is the thing you're trying to avoid.

And what makes the ball move sideways 1"? Force...with a longer rear overhang it will take less force to move the ball 1" than with a shorter overhang. If the ratio of the overhang to the wheelbase is the same, it will take the same force to move the ball 1". That is the case with the Suburban and Tahoe.

I'm not sure exactly what you're saying but I think you're supporting my point. If the same force will cause the same 1" movement on 2 different wheelbases (but with the same overhang/wheelbase ratio), the longer wheelbase one will have yawed at a smaller angle which is more desirable.

wnjj wrote:
The longer wheelbase has an advantage even with the same overhang ratio. Suppose the hitch ball is suddenly pulled sideways 1 inch. With the same ratio on both vehicles the front will try to slide over the same amount on both vehicles to compensate BUT the longer wheelbase one will result in a smaller yaw ANGLE which is the thing you're trying to avoid.

And what makes the ball move sideways 1"? Force...with a longer rear overhang it will take less force to move the ball 1" than with a shorter overhang. If the ratio of the overhang to the wheelbase is the same, it will take the same force to move the ball 1". That is the case with the Suburban and Tahoe.

I have not towed with each, but I love my 2500 Suburban.

Your 6300 lb dry weight is a little more than my 5900 lb dry weight. I've never weighed the whole trailer, but I've weighed my tongue and it was 1200 lbs. Over the receiver limit on any 2007+ Tahoe or Suburban. You would need to be careful on loading no matter what.

Even if you can keep the TW under 1,000 lbs to satisfy the receiver limits, you will likely be at or over the GVWR and rear axle rating of any 1/2 ton. It would be great if you could get the tow vehicle and trailer, load them up and weight everything before you have to buy them. Sadly that is not the case. What is the dry weight tongue weight? The ratio of dry TW to dry trailer weight of the trailer often will remain the same or increase (depending on where stuff gets loaded) as you load for camping. Might help you guess on loaded tongue weight. If you pull with fresh water and the tank is in front of the axles, it will cause your ratio to go up. If most of the storage is in the front, the ratio will go up as you load. I have a lot of storage in front, little in rear, and my water tank is over the axles. My ratio went up.

You need to carefully consider if a 3/4 ton is a requirement. It might be.

ktosv wrote:

rockhillmanor wrote:
It is not 'perceived'.

That extra few inches of wheelbase DOES make a difference

I guess that is my point. Everyone states it is the wheelbase that improves the handling. In the case of the Suburban, it must be some other function of the vehicle that makes it a better tow vehicle as the ratio of the rear overhang to the wheelbase is nearly identical to a Tahoe. Therefore based on physics both vehicles should tow very similar.

Just out of curiosity, did you tow with a Tahoe and then move to a 1/2 ton Suburban? I know the post from Crabbypatty lead me to believe they went from a Tahoe to a 3/4 Suburban and saw a difference. But I can tell you that towing with a 1/2 ton Suburban and moving to a 3/4 ton Suburban is night and day as well.

In the end, this probably is a moot point as the OP really needs to be looking at payload capacity if they are truly looking at a trailer with a dry weight of 6300#. Unless it is a family of two, they will most likely be exceeding some ratings in a half ton Suburban/Tahoe.

The longer wheelbase has an advantage even with the same overhang ratio. Suppose the hitch ball is suddenly pulled sideways 1 inch. With the same ratio on both vehicles the front will try to slide over the same amount on both vehicles to compensate BUT the longer wheelbase one will result in a smaller yaw ANGLE which is the thing you're trying to avoid.

In my experience, the added wheelbase of the Suburban is a plus, but the biggest improvement came from going from a 1500 Suburban to a 2500 Suburban. I've had all 3 and won't go back to a shorter wheelbase or a 1/2 ton again.

That's been my dilemma in recent years... My 2005 Suburban 2500 8.1L is a towing beast, but I'm ready for something newer. However, GM stopped making 2500 SUV's, and I've been at a loss as to what I would like to buy next.

After a lot of research, the GMC Yukon XL Denali and the Cadillac Escalade ESV have a lot of the heavy duty parts that came on the 2500 Suburbans - bigger motors, heavier brakes, HD transmissions, heavier axles, etc..., and enough towing capacity for all of my trailers except my 5th wheel.

I've just ordered a 2015 Yukon XL Denali with a 6.2L 8-speed. 420hp and 460 lb-ft of torque, and the latest magazine articles reported 21 MPG in 4x4 version. I'll be listing my 2500 Suburban as soon as my GMC comes in.

rockhillmanor wrote:


I see you tow with a van. I towed my horse trailers with a van. IMHO it is one of THE best tow vehicles and do wonder why more RV'ers don't use them.

Yep, I've been towing with full sized Ford Vans since 1979, first an E250 and now the one in my sig. I've towed a hard sided APACHE PU, then a 26' ultra high Prowler bunkhouse and now the 32' one in my sig. IMO if you go with a 1T you can't beat the payload capacity and people carrying capacity unless you go with a DRW PU. One key IMO is you have to load the Van down so the DOG has some GUTS. IMO having the TV weigh as much and preferably more than what you are towing is as important as the WB and/or type of hitch. When we are "LOADED" for one of our 1 to 2 mo roadtrips my Van weighs well in excess of 2,500 lbs more than what is on the TT Axles.

Biggest issue is to get a good Van TV you will probably have to buy new and either go the cargo route and then spend the $$$ to set it up to your needs. That's what I did with our current Van and couldn't be happier.

Mine still won't win any races but that is not a power issue but an EGT limitation due to the lack of an intercooler and the "can of sardines" under the hood. The security and payload carrying flexibility is unmatched by any other TV IMO.

Larry