Power Needed to Drag a Trailer Through the Backcountry

[Cortttt]

I'm transitioning from a GMC van with a 4.8L engine and a limited-slip that I've been boondocking in for quite a while to another Chevy/GMC van with 4wd and probably a locker towing probably a 3-5000 lb. trailer. Besides having 200K on it the present van doesn't do well on steeper hills and clearly doesn't have the power to tow a trailer when it gets a little sketchy (sandy, muddy).

I have no experience at all with 4wd. My question is how much power do I need to get that trailer through the somewhat sketchy dirt roads that I encounter in the desert and sometimes in the mountains. Since it looks like it's going to be a Chevy the power possibilities are:

• 2.8L - 181@4200 hp; 369@2000 Torque; Towing capacity - 6000
• 6.0 L - High: 362 hp @ 5400 RPM; 360 lb-ft @ 4000 RPM; towing capacity - 10,000 -
• 6.6l - 401@5200; 464@4000, towing capacity - 10,000

The 2.8 is enticing because of the good MPG but I don't know if has the pulling power. I think, but don't know, that the 6.0 has good low-end torque. The 6.6l has better mpg than the 6.0 and excellent low end torque.

I believe they all have 3.42 gears.

Any ideas would be welcome

 

[NatersXJ6]

It depends on how fast you want to go. In my experience, you will struggle more with freeway traffic and mountain roads at speed if you are under-torqued. Staying in lower gears means more rpm and more fuel, but if you are running slow on the back roads anyway, you never get to the higher gears where the low end torque really matters.

 

[stevo_pct]

I know this isn't really your question, but I've been looking into this a lot and I think the limit would be the trailer itself. Regardless of the power your truck has, your trailer will get beat to hell if you're towing it any distance on rough dirt roads. And it would be a really unpleasant ride. But if, like a lot of RVers, you're only going a few hundred yards, it wouldn't be that big of a deal.

At least this had been my experience. I like to get far off the beaten track and I hate having to drive 5mph or less because my trailer is getting slammed all over the place.

All that said, I think the power limitation would come into play more on the highway going over mountain passes. For a 4000-5000# trailer, I would go with the 6.6L.

 

[Cortttt]

I know this isn't really your question, but I've been looking into this a lot and I think the limit would be the trailer itself. Regardless of the power your truck has, your trailer will get beat to hell if you're towing it any distance on rough dirt roads. And it would be a really unpleasant ride. But if, like a lot of RVers, you're only going a few hundred yards, it wouldn't be that big of a deal.

At least this had been my experience. I like to get far off the beaten track and I hate having to drive 5mph because my trailer is getting slammed all over the place.

Thanks. It's going to be a well-built off-road trailer like an OBI Dweller, Opus 15, Taxa Mantis - that's able to withstand quite a bit of punishment and takes me a good distance into the backcountry.

 

[Cortttt]

It depends on how fast you want to go. In my experience, you will struggle more with freeway traffic and mountain roads at speed if you are under-torqued. Staying in lower gears means more rpm and more fuel, but if you are running slow on the back roads anyway, you never get to the higher gears where the low end torque really matters.

The problem with the current van is that it poops out in certain situations - like some hills on dirt roads. It's kind of surprising how little it takes to cause it to do that. I need something with enough grunt to power through those situations with a trailer.

 

[stevo_pct]

Thanks. It's going to be a well-built off-road trailer like an OBI Dweller, Opus 15, Taxa Mantis - that's able to withstand quite a bit of punishment and takes me a good distance into the backcountry.

I'm interested in what kind of trailer you're looking at.

 

[Cortttt]

I'm interested in what kind of trailer you're looking at.

As per my partners wishes - make that demands - it's got to have an interior shower and toilet. We don't want anything much over 5K weight and lighter is better. I was strongly encouraged by a dealer not to try to drag any trailer that weighs 6K or more through the backcountry with that van.

After talking to two dealers who stopped selling Black Series trailers because of quality issues we're focused on the OBI Dweller, the Opus 15, the Taxa Mantis, the Airstream Basecamp, and the RKS PurposeMotive.. The OBI Dweller is really nicely designed but is quite heavy (about 5K without water) and has low payload - so its probably out. The Airstream Basecamp has a great lounge area and design as well. My one question with it is how much punishment it can take. Despite the fact that you can't stand up in it we're also interested in the RKS Purpose right now - light and with a popup shower. The Anti-Shanty REALLY caught our eye - loved that design - but unfortunately didn't have an indoor shower.

 

[gendlert]

Don't get the 2.8. You will want more towing margin than that to pull a ~5000lbs trailer. The taxa might be ok, but the other two will be too much for that rig. The other two options will be fine.

Sent from my Pixel 5 using Tapatalk

 

[NatersXJ6]

It’s just a really hard question to answer, especially as you talk about 200k miles. Will your new van be new? When you say “poops out”. What does that mean? For instance, my Jeep needs 3000+ RPM to maintain a 50 mph climb up some of the long mountain grades in the Sierras in 3rd gear. There are people that can tell you a 3.6l v6 should happily run 3k all day long, but my experience has been that is a good way to blow another oil cooler, so I would rather have more torque and stay around 2k. That ain’t gonna happen. Putting my trailer on means 3500 RPM and 35 mph up the same grade. On trail or side roads, I’m happy to run 20 mph and enjoy the day. But the grades I’m talking about are 4 lane highways. Not acceptable. I’m trying to diagnose problems but believe the engine is simply lacking torque and staying in low gear.

others are happy to run 4K rpm and fly by me like I’m standing still.

real world versus paper performance is all in the eye of the beholder.

 

[Cortttt]

Don't get the 2.8. You will want more towing margin than that to pull a ~5000lbs trailer. The taxa might be ok, but the other two will be too much for that rig. The other two options will be fine.

Sent from my Pixel 5 using Tapatalk

Thanks. That's been my suspicion. My guess is that I want to go at least a couple of thousand pounds below towing capacity.

 

[Cortttt]

It’s just a really hard question to answer, especially as you talk about 200k miles. Will your new van be new? When you say “poops out”. What does that mean? For instance, my Jeep needs 3000+ RPM to maintain a 50 mph climb up some of the long mountain grades in the Sierras in 3rd gear. There are people that can tell you a 3.6l v6 should happily run 3k all day long, but my experience has been that is a good way to blow another oil cooler, so I would rather have more torque and stay around 2k. That ain’t gonna happen. Putting my trailer on means 3500 RPM and 35 mph up the same grade. On trail or side roads, I’m happy to run 20 mph and enjoy the day. But the grades I’m talking about are 4 lane highways. Not acceptable. I’m trying to diagnose problems but believe the engine is simply lacking torque and staying in low gear.

others are happy to run 4K rpm and fly by me like I’m standing still.

real world versus paper performance is all in the eye of the beholder.

I know! It's all about real world experience. A dealer told me of a guy who brought a brand new Tundra and was miserable trying to tow a HQ19 despite the fact that it was well under its towing capacity. That kind of scared the crap out of me

The 200K van will, somewhat sadly, be gone. It'll be a new van or own built from 2015 onward.

Poops out. The rear wheels refuse to turn. They're not stuck - they just won't go anywhere. This happens on some hills. Can't imagine pulling a trailer with this thing even if it has a 10,000 pound towing capacity. It's got no low down grunt. It's always been a poor accelerator; it's starts to really start moving at about 40 mph. it does OK on mountain hills (without a trailer) but its in the dirt that it craps out. Hence the desire for low end torque to keep it and the trailer moving in the dirt. How much I need I don';t know.

 

[NatersXJ6]

Yep, it sounds like a well-worn transmission! Similar to what I think my issue is here.

In that case, pick the 6.6L. They always say “there’s no replacement for displacement” although my eco boost 3.5L is making that statement show its age. Good luck. It is hard to go wrong with choosing the biggest option, although you will get poor mileage all the time instead of only when towing.

 

[billiebob]

I'm transitioning from a GMC van with a 4.8L engine and a limited-slip that I've been boondocking in for quite a while to another Chevy/GMC van with 4wd and probably a locker towing probably a 3-5000 lb. trailer. Besides having 200K on it the present van doesn't do well on steeper hills and clearly doesn't have the power to tow a trailer when it gets a little sketchy (sandy, muddy).

I have no experience at all with 4wd. My question is how much power do I need to get that trailer through the somewhat sketchy dirt roads that I encounter in the desert and sometimes in the mountains. Since it looks like it's going to be a Chevy the power possibilities are:

• 2.8L - 181@4200 hp; 369@2000 Torque; Towing capacity - 6000
• 6.0 L - High: 362 hp @ 5400 RPM; 360 lb-ft @ 4000 RPM; towing capacity - 10,000 -
• 6.6l - 401@5200; 464@4000, towing capacity - 10,000

The 2.8 is enticing because of the good MPG but I don't know if has the pulling power. I think, but don't know, that the 6.0 has good low-end torque. The 6.6l has better mpg than the 6.0 and excellent low end torque.

I believe they all have 3.42 gears.

Any ideas would be welcome

Its not about power, it is about gearing. Most vans are geared for the highway thinking of low rpms to quiet the ride and extend the range.

Steep hills need a deeper rear end ratio.
Steep downhill on forestry roads are easy with deep gearing, maybe 4.10 rear ends AND a 2 speed transfer case.
Are you talikng a 4WD conversion with a 2 speed transfer case?? Or an AWD Chev/GMC with a single speed full time "transfer case".

Most 4WD driving has no need for power to accelerate. It is all about control with real low gearing.
Hard to meet all the goals. Interstate travel vs Moab Trails.
GMC AWD vans are incredible overlanders.
But gear it for what you do.

Regearing the van you have might give the performance want.
If its 2WD,,, add a locker at the same time.

 

[Obsessed2findARuggedHybid]

Thanks. It's going to be a well-built off-road trailer like an OBI Dweller, Opus 15, Taxa Mantis - that's able to withstand quite a bit of punishment and takes me a good distance into the backcountry.

If you go Mantis it would have to be the Overland and I believe they are 3,500 plus dry and 5,200 gvw. Not sure I would trust them for to hard of off roading. RKS look awesome in regard to build quality and bathroom. But a lot of money for a non stand up rig. Boreas Eos12 is 75k but a consideration. Mission Overland, RKS and High Altitude Trailer are coming out with stand ups but will be heavy and expensive. I decided on Trailer Marker Up and Out with wet bath. Not your typical build. More rustic

 

[Cortttt]

Thanks. One of my big questions. The gearing is 3.42 - very low on grunt I take it. Pretty good at higher speeds but not from standing still.

I was thinking of 4HI/4L0 4wd possibly with a locker. Maybe re-gearing will be necessary. I'll have to check out options.