Towing with 4.8 or 5.3

Discussion in 'Chevy Silverado Forum (GMC Sierra)' started by inhaliburton, Mar 27, 2011.

  1. inhaliburton

    inhaliburton New Member

    Hi there, I'm a converted Ford truck person, so I do not know much about GMC. I'm dealing a 2010 4.0 V-6 Ranger for a 2008 Sierra 5.3 Z-71.

    Am towing a hybrid RV trailer that weighs about 4000 lbs. The Ranger struggles with this, hence the reason for switching to a Sierra.

    Would it be a struggle to pull this weight with a 4.8? There are some lovely extended and crew cabs at the same dealership, and somewhat less expensive.

    Also, would you hazard a guess at the rear axle ratio?

    Are there any other considerations that I haven't thought about? I'm not wanting to make the same mistake twice by purchasing an underpowered truck.

    Thanks, I appreciate your advice and expereience.
    Last edited: Mar 27, 2011
  2. pmf608

    pmf608 Epic Member 5+ Years 1000 Posts

    I think a 4000lb trailer would do fine behind a 4.8 or a 5.3. I have had experience with ford's 4.0 v6 in the mustangs and I personally find it a weak engine, especially in comparison to gm's v8 engines. I have the 4.8 in mine and have had it pretty well loaded a few times and never had a problem. I think you will find more of the 4.8 trucks will have 3.23 and 3.42 axle ratios, but I would suggest at least a 3.73 I you plan on towing that trailer often. A 4.10 would be the ideal for towing, but may be a bit more than you will need for that trailer. If you can afford it, it may be worth looking into a 2009 with the 5.3 so you can get the 6 speed automatic, in which case the 3.43 axle would e about equal to a 3.73 in the 08. I hope this helps. Make sure to let us know what you end up with. I am sure you will be very happy with any of them coming from a ranger
  3. inhaliburton

    inhaliburton New Member

    I hadn't thought of that! That 6-speed tranny would be great.

    I drove a 2008 5.3 Z71 extended cab today and was very impressed. At 100 kph, it was reving at 2000 rpm, which seemed a bit high to me. Would you care to guess at the rear axle ratio?

    I had a scanguage II hooked up to it and on the highway into the wind it did 17 mpg and on the return trip with the wind I got 21 mpg.

    Thanks for your help.
  4. pmf608

    pmf608 Epic Member 5+ Years 1000 Posts

    2000 rpm is around normal for tear trucks at that speed (with the 4 speed anyway). At 110 kph in my 4.8 with the 3.42 rear end, I run just under 2000, so that would probably be a 3.73 in that truck. These trucks are fairly efficient at that rpm range since it's not low enough to lug or high enough to waste power. I personally haven't driven a gas truck with the 6 speed in it, but the people who have them generally like them. The 6 speed would get better gas mileage because the double overdrive allows lower rpm at highway speeds and an intermediate gear that will give you similar performance. I believe the gear ratios will also allow for better acceleration too. The gearing of the 6 speed also makes shorter rear end gearing equivalent to taller gearing with the 4 speed.

    Regardless of what engine/transmission you end up with, as long as you get 3.42 gears or better, it will be many many times better than the antiquated ford 4.0 and shouldn't have any problem with a 4000lb trailer

Share This Page

Newest Gallery Photos