Tow Vehicle Options

wlanford · 10-16-2002, 03:21 PM

At retirement, my wife and I are considering the purchase of a 28' or 30' Airstream Excella for nationwide touring. For a tow vehicle, we are considering the Suburban/Yukon XL 3/4-ton with the 8.1L engine. This vehicle would also be our 2nd car and would be driven in-town when we're not "on the road". I 'm not sure whether the 3.73 or 4.10 rear-axle would be the best choice! It seems to me that the 3.73 would be fine, but I have seen several posts which stated that "you can't have too much tow vehicle". But I worry that the 4.10 would drink too much gas when driven around town! Recommendations?

Thanks in advance!

Les Gilliam · 10-16-2002, 04:43 PM

I pull a 28ft Excella with a 3/4 ton Suburban 8.1 and 3.73. I am sure the 4.10 would pull better, but mine handles very well and I am quite satisfied with it. The mileeage isn't all that good averaging 9 mto 12 gph with tow and 11-14 without tow. A lot depends, of course, on speed and terrain. My dream tow vehicle would be a 3/4 ton Suburban with a Duramax engine and an Allison transmission. Too bad they don't make them.

davidz71 · 10-16-2002, 04:58 PM

My '01 Chevy 2500HD extended cab truck has the 8.1, Allison trans and 3.73 rear end. It pulls my 31' Excella 500 fine. I get either side of 15 mpg on the interstate without AC and 10 in town with AC running. I get 12-13 towing. If you are running LT245-75-16 tires then the 3.73 rear is fine, helping get better gas mileage when not towing. If you plan on putting on taller tires such as LT265-75-16 or LT285-75-16 then I would go with the 4.10 rear. These recommendations would hold with your Suburban as well. If I decided to tow nationwide then I would probably get the same truck I have now but get it with the Duramax diesel available in the 2500HD for better gas mileage.

j54mark · 10-16-2002, 04:59 PM

The 3.73 should be fine for any 28 or 30 foot Airstream - except perhaps the 30 foot slide-out model. The nice thing about a 3.73 is that it runs at highway speeds at a lower and quieter rpm. And the gas milage is better too.

The only exception would be if you actually live in and frequently tow in mountains.

Mark

John · 10-16-2002, 05:01 PM

I went from FL to BC,Canada towing a 1994 28' Excella with a 2000 K-1500 5.3L with 4:10. I got 13 mpg on the hwy and 10.5 mpg in the mountains. It's in the rear greaing. Of course on those steep grades, I traveled at 35 mph @ 2500rpm.
Good Luck, John

jlovelady · 10-16-2002, 08:21 PM

I traded in a Dodge 2000 with a Cummins engine and a 3.54 rear end on a Chevy Crew Cab Silverado with an 8.1 L. It has a 4.10 axle.
I love the truck. It is very quite and roomy. I miss the torque of the diesel but not the noise. Like you, I use the truck as a second vehicle at 13 mpg on the road without a trailer. When I pull my 34' 1993 Excella I get 10.2 mpg whether I am on flat or mountainous terrain.

I would now prefer a 3.73 for better milage when I am not pulling. I don't think it is available with the 8.1L gas and an Allison transmission.

The transmission is the best. It will respond to braking and stay on a constant downhill speed. You can then let off the brake and let the automatic transmission do the work without actually having to downshift.

Excessive oil consumption is a problem on the 8.1L. Mine uses 1 quart each 1,000 miles. GM says that is normal. We are now under an oil consumption test. It does not seem to effect performance.
Best of luck.

RoadKingMoe · 10-16-2002, 08:59 PM

Quote:

Originally posted by davidz71
My '01 Chevy 2500HD extended cab truck has the 8.1, Allison trans and 3.73 rear end. It pulls my 31' Excella 500 fine.

Given same tires, Allison tranny, and 3.73:1, the 8.1 in fourth gear is putting about the same torque to the ground as the Isuzu Duramax is in fifth, and the 8.1 in third gear is about the same as the diesel in fourth. The gas engine both gets its peak torque at 100 higher rpm than the diesel gets its peak hp, and the gas engine can be run at that rpm a lot longer than the diesel can. Of course, that's partially why it uses a lot more fuel.

Quote:

I would probably get the same truck I have now but get it with the Duramax diesel available in the 2500HD for better gas mileage.

If you tried to calculate its GAS mileage, you'd get a DIVIDE BY 0 error.

davidz71 · 10-16-2002, 09:46 PM

Seems about right Maurice.

davidz71 · 10-17-2002, 07:49 AM

jlovelady,
The 8.1 with Allison and 3.73 is available in the 2500HD 2WD and 4X4 in the reg. cab, ext. cab and the crew cab. It is not available in the 3500 2WD or 4X4.

'63 princess · 05-23-2005, 09:54 AM

I have a 26' 1963 Overlander. Do I need all that? The Duramax engine, the Allison tranni and the 4.10 rear end?

I understand that the transmission is the most important element when deciding on towing vehicles...

8.1, what does that mean, V8? Do I need that much? Wouldn't 5.3 cylinders be alright for the 26'?

Granted; I plan on putting a lot of cool stuff in it including a 60's fridge and possibly an older stove.

overlander64 · 05-23-2005, 12:18 PM

Greetings '63 princess!

Quote:

Originally Posted by '63 princess

I have a 26' 1963 Overlander. Do I need all that? The Duramax engine, the Allison tranni and the 4.10 rear end?

I understand that the transmission is the most important element when deciding on towing vehicles...

8.1, what does that mean, V8? Do I need that much? Wouldn't 5.3 cylinders be alright for the 26'?

Granted; I plan on putting a lot of cool stuff in it including a 60's fridge and possibly an older stove.

I tried skimping on the tow vehicle that preceeded my current K2500 Suburban with the 7400 VORTEC and 4.10 differentials (7.4 liter predecessor of the 8.1 in use today). My previous tow vehicle, a K1500 Chevrolet Club Cab Z-71 pickup with the 5.7 Liter V8 and 3.73 differentials, was overwhelmed by my '64 Overlander -- fully loaded for an extended vacation, my Overlander tips the scales at 6,100 pounds (Empty Weight 4,440 pounds) and that was more than 94% of the factory trailer tow rating for that particular K1500 pickup truck.

Particularly if you are planning on adding additional options/accessories that will increase the weight of your coach, a large displacement V8 with 4.10 differential gears will be a noticeable improvement in towing comfort (IMHO). The slight difference in solo fuel economy wasn't worth the trade-off in towing performance (IMHO). In fact, my Suburban with the 7400 VORTEC produces better fuel economy figures both solo and when towing than my K1500 Chevrolet pickup ever did in the 45,000 miles that I drove it (the Suburban just turned 142,000 miles yesterday from day I took delivery in 1998).

Good luck with your investigation!

Kevin