We have a 2005 Avalanche 1500 with the small V8 in it and it has a towing capacity of 8000 lbs.
Today, we went to a dealer and did a test pull of a new Startcraft Autumn Ridge which weighs 4700 lbs. empty.
We thought with the Avalanche's 8000 pound rating, we would have plenty of power to pull a 4700 lb. trailer,
We were very disappointed, the acceleration was very poor, in fact I had the accelerator floored and when we reached 65 mph we seemed to be not accelerating any more.
Does anybody have any ideas ? Is 4700 lbs. too much for our truck or is there something wrong with it ?
When you say the small V8, there is only one engine available in the Avalanche and that is the 5.3. Knowing the rear end will help alot. If you don't know the rear end i can pull it with the last 8 characters of your VIN number. My guess is the trailer is alot heavier than what you posted, meaning the salesman told you a fictious weight which there very know for that.
* This post was
edited 04/28/12 03:46pm by dspencer *
If that is what happened during your test tow, there is something wrong with your Avalanche. Did you have it in OD or D? Tow haul on or off? Is your Avalanche 2wd or 4wd?
We towed the trailer in our signature with a 1/2 ton 05 Suburban with the 5.3L and 3.42 axle. My trailer weighs 5400# empty and the Suburban did fine with it empty. I can also tell you that loaded, it was slower from a start but I could easily get over 65mph.
Kevin and my...
Wife and four kids
and two dogs(brittany and english setter)
2011 Express 3500 (6.0L/6A/3.42)
2010 Passport Ultra Lite 2910
You may be wrong about your tow rating as spencer noted.
Even if you are correct about your tow rating you have discovered what a lot of people do. There is a big difference between rated to tow a certain weight and actually having an enjoyable time behind the wheel towing a certain weight. A trailer that is 4700 pounds empty will gain 1000 or more pounds when you add your "stuff" to it. Factor in some firewood, coolers, and bikes in the back of the Avalanche and you'll have quite a load.
In my experience that is not enough engine to enjoyable tow that load.
ib516 wrote: Is probably the axle ratio that's killing towing performance. I'd guess its a 3.42.
Look in the glove box at the rpo codes sticker.
GU5 is 3.23
GU6 is 3.42
GT4 is 3.73
GT5 is 4.10
Higher numbers are better.
X2. The 5.3 is more than enough to tow upwards of 7k. I had 4.10 gears in my 03 Tahoe 4x4 and pulled thousands more than you were...and had acceleration left over.
2006 Chevy 2500HD 8.1 4x4 CCSB
2012 Eclipse Stellar 28SBG, Spring Over Axle
Hmm straight from the manual: 7100 for 4x4 and 7300 for 2x4.
Both require either tow or off road package for anything over 5000.
I suspect that trailer is over 4700 and you would need to be using tow haul mode.
Avalanches are heavy by nature and I suspect that you would be close to the GCWR with anything close to 5000. I had an 03 essentially the same as an 05 it towed a 6000 lb horse trailer just fine using tow haul. mine was a 4x4 with 373 gears.
If yours is a 4x4 with 410's it sure ought to pull that trailer unless there is a lot of frontal area.
You don't have some of god auful oversize tires on it do you?
Maximum trailer weight is calculated assuming the
driver and one passenger are in the tow vehicle and it
has all the required trailering equipment. The weight
of additional optional equipment, passengers and cargo
in the tow vehicle must be subtracted from the
maximum trailer weight.
Above the 5,000 lb (2 268 kg) trailer rating, the
handling/trailering suspension is required on
C-1500 models and the handling/trailering or off-road
suspension is required on K-1500 models.
Notice: Using a fifth-wheel or goose-neck hitch
device on your vehicle could damage the vehicle.
The repairs would not be covered by your warranty.
Do not use a fifth-wheel or goose-neck hitch
device on your vehicle.
Vehicle Axle Ratio Maximum Trailer Weight **GCWR
C-1500 (2WD)
5300 V8
3.42 7,300 lbs (3 311 kg) 13,000 lbs (5 897 kg)
4.10 8,200 lbs (3 719 kg) 14,000 lbs (6 350 kg)
K-1500 (4WD)
5300 V8
3.42 7,100 lbs (3 220 kg) 13,000 lbs (5 897 kg)
4.10 8,000 lbs (3 628 kg) 14,000 lbs (6 350 kg)
**The Gross Combination Weight Rating (GCWR) is the total allowable weight of the completely loaded vehicle and
trailer including any passengers, cargo, equipment and conversions. The GCWR for your vehicle should not be
exceeded.
Vehicle Axle Ratio Maximum Trailer Weight **GCWR
* This post was
edited 04/28/12 04:42pm by Tombstone Jim *
2011 Big Country 3450
06 F250 4x4
91 Wrangler
2011 Jeep Liberty
Appreciate the followup, here are a few answers to the questions that have been asked :
Decoding the axle code, it is a 3.42 ratio axle as predicted.
It is a 2WD
I was using the trailer mode while towing.
Here are a few questions:
1) Could the engine be starved for fuel, like a clogged fuel filter ?
2) Could the catalytic converter be partially plugged ?
3) Could the axle gear ratio be changed ? I assume if this was changed the speedometer would need to be modified as well ?
I did look at the factory sticker which does vwerify the exact weight of the trailer when it left the factory and it was about 4700 lbs.
It did pull with no problem at speeds below 50 mph. it was accelerating to highway speeds that had me very concerned, it seemed like the truck was working very hard and didn't think this would be good for the truck long term.
You should not be having problems towing 4,700 lbs as you indicate. However you may have some misconceptions on how it will run with your set-up. DW towed a 6,000 TT with an 05 Tahoe 3.73 ratio for tens of thousands of miles with no problems. However must of that time was spent in D (not OD) running at or over 3,000 rpm. With a 3.42 ratio I doubt you will ever see OD except downhill. Just put it in drive and go. If it doesn't pull in drive around 3,000 rpm at highway speed easily then you have something wrong with the truck.
BTW don't worry about reving that engine up and let it run that way for long periods of time. It is designed to run like that and does very well. That '05 tahoe is still on the road with 140,000 miles and still runs like it is new. DD has it now and loves it.
I think the main problem is your expectations. The 5.3L with 4-spd and 3.42 means 3 useful towing gears. WOT should be 1st and 2nd gear accelerating to 65mph, then 3rd gear cruising at 2400rpm. That's normal.
To significantly improve acceleration, you need something new enough with 6-spd transmission or a lot more power or both).
But the Avalanche has low payload. 4700 pounds dry and 5500-6000 loaded will likely overload the truck's GVWR with a family onboard.
A & A parents of DD 2005, DS1 2007, DS2 2009 2011 Suburban 2500 6.0L 3.73 pulling 2011 Heartland North Trail 28BRS 2012 VW Passat TDI
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