How Long is too long

It depends on how the Burb is set up. I towed a similar sized trailer with a Dodge conv van. But it had the 5.9L and 3.90 gears. If the Burb is properly equipped it will do well. We need more info such as motor and gears as well as what it’s rated to tow.

Have you measured and then checked wheelbase charts?

It has the 5.3L and 3.73R from what I gather it's rated at 7400

I'd be more concerned with weights than length. We tow a 35' unit with our Suburban 2500 and wouldn't blink at going longer if we wanted to. We have no issues whatsoever. That said, we have the 2500 'burb with the 8.1L engine and the 4.1 gears - so we are well within all of our ratings (8k trailer weight out of a 12k tow rating, 1,110 lb tongue with 2,200 pounds of payload, etc...). My concern, on your end, is that you MAY be able to stay within your tow ratings, but could struggle to stay within payload with a 31' trailer on a Suburban.

I'd focus on those numbers, instead of length, and see how they play out - that will tell you a lot.

I'm not sure what you mean by "but could struggle to stay within payload with a 31' trailer on a Suburban.

Even with a good WD hitch properly setup I would not do it. Loaded with family coupled with P metric tires and a really soft suspension combined is plane asking for problems when, not if you find yourself in a sticky situation. Just loaded with family 1500 Suburbans typically are at their weight limits without adding hitch weight.

Folks will tell you length is an issue, but they will not produce a formula or any data to support such a claim.

They will also tell you a full size extended cab 6.5' bed 1500-series pickup is too short to tow, but a full size extended cab 6.5' bed 2500 or 3500-series pickup is plenty long enough. THEY ARE THE SAME EXACT WHEELBASE AND LENGTH.

Weight is the issue. Ideally you should find out your weights now and see just how far over the ratings you are already, before deciding on an even heavier trailer.

IMHO 7000lbs is about all you really want to tow with a 1500-series truck or suburban and expect reasonable comfort. You can often tow more but it quickly becomes less and less comfortable to drive long distances.

Notice I said NOTHING about "safety" up to this point. Safety is rarely the issue. You will get annoyed with the lack of comfort long before you put yourself or anyone in any danger more quantifiable than simply hitting the road with the family in the Suburban to go to church on Sunday.

mkirsch wrote:
Folks will tell you length is an issue, but they will not produce a formula or any data to support such a claim.

They will also tell you a full size extended cab 6.5' bed 1500-series pickup is too short to tow, but a full size extended cab 6.5' bed 2500 or 3500-series pickup is plenty long enough. THEY ARE THE SAME EXACT WHEELBASE AND LENGTH.

Weight is the issue. Ideally you should find out your weights now and see just how far over the ratings you are already, before deciding on an even heavier trailer.

IMHO 7000lbs is about all you really want to tow with a 1500-series truck or suburban and expect reasonable comfort. You can often tow more but it quickly becomes less and less comfortable to drive long distances.

Notice I said NOTHING about "safety" up to this point. Safety is rarely the issue. You will get annoyed with the lack of comfort long before you put yourself or anyone in any danger more quantifiable than simply hitting the road with the family in the Suburban to go to church on Sunday.

If weight is the issue,than safety quickly becomes the issue.
An overloaded rig is unsafe.

Your biggest problem will be rear end squat with that rig. Even if your within specs, it will likely settle more than is safe for good handling.
If you proceed, prepare yourself for possible rear suspension upgrades.

If you have to ask, then it may be a bit much for you, but not the truck.
I hook my 6000lb boat, 32’-7000lb sled trailer and heavier flatbeds than that with a 1500 Silverado. Prefer the Dodge but the little Chev does fine with it.
2016 5.3.

You’ll probably want a little help with the rear springs, I prefer stiffer tires but P tires work and I wouldn’t leave out a wdh since it could be too much tongue weight for long distance towing.