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QUESTION ON BEST MODS!! To improve Towing

PS600REVX

Full Member
Joined
Jan 3, 2013
Messages
17
Ok, here we go. New to the forum but I have had my 2003 Z71 for just over a year now.  Never had a real question before but now I do.  I have an approx 6500 lb loaded up travel trailer.  I have towed it with the Av a couple times and it does ok I guess.  The Av was always the backup tow vehicle as my wife has a Nissan Armada which is an absolute beast as far as power and towing and the Av is just not.  No offense to hardcore Av or GM truck guys but I'm pretty sure nobody ever claimed the 5.3 is too powerful.  Anyhow, now my wife is getting a smaller vehicle and the Av becomes #1.  Anybody that has had real experience with doing mods with the purpose of adding towing power feel free to chime in.  What do you suggest?  CAI I believe will probably be the #1 recommendation and I plan on adding that 1st and probably will go with the K&N as I hear they are the best and I don't care about the look of it so don't need stainless, etc.  Beyond that what?  Hand held tuners?  I have done this in the past to other vehicles and to be honest, was never really impressed but if you have experienced good things let me know.  Cat Back?  If so, which one?  hate hate hate ridiculous droning in the cab.  Don't mind a little grunt but don't want to go deaf towing 400 miles.  Again, feel free to chime in if you have had real world results where you could feel a difference in the towing.  Thanks all.
 
Well, since no one else has offered any suggestions, I'll toss a hat in the ring.

6,500 lbs is a lot for a 1/2 ton AV.  No matter what the towing guides say, just about every person who has posted credible sounding experience towing over 6,500 lbs with any of the 1/2 ton GMT800 products has been seeking a better towing experience.

Once the sunshine of advertiser claims and user seat of the pants expense justifications settles into the hard cold reality of truthful night, you will not find much power that was left on the table and now is found with simple engine bolt ons.  GM did not leave any low hanging horsepower on the tree.  The stock GM air cleaner flows all the air that the 5.3 can use, and GM's stock exhaust is actually superior in a balance of traits than most aftermarket ones.

The engine is not the only issue though.  The transmission is weaker, and the rear gear is likely taller (weaker) to be more fuel efficient.  And that's all just the go department.

Then there is the stop department.  Brakes.  What if the electric trailer brakes fail... how robust are the 1/2 ton brakes in the event they need to handle all the stopping duty in an emergency?

If towing is high on your agenda, it may be worth while to put all the money you were thinking of pouring into fixing your AV into a shoebox instead... while scouring the lots, eBay, craig's, and other avenues of the net for a 3/4 ton AV.  Then trade your AV and that shoebox for a tow vehicle better suited to tow a 3 ton plus box behind you.
 
First welcome to the site.
I agree with a lot that CoveredAV has said.

I would not waste money on a CAI since you will only increase the acceleration noise and not get any real gain in towing torque. Your Z71 should already come with a high flow aircleaner but if you want to change try to save yourself some aggravation by buying a dry version, not the kind of filter you need to oil. Some people have over oiled their filters and damaged their sensor and led to motor problems.

One big thing is to find out what is your gearing in the rear. If low like a 3.42 you may want to swap gears to get a 4.10 rear. Make sure you turn on your tow/haul mode also to improve shift points.

If you have the funds consider getting a Magnacharger supercharger. They have a great bolt on kit that really wakes up the 5.3 for towing.


For a CAT back exhaust I would recommend a Corsa Sport or the Touring model for absolutely NO Drone. The exhaust is the first mod I have done back in 2004 when I got my first AV and again in 2008. I find that getting a good CAT back system does increase power and acceleration. I would get a Corsa before I spent money on a CAI or a Tuner.

Brakes are sometimes an issue on first generation AVs and several members here have switched their first generation AV brakes for the second generation AV ones with good results. There are threads on this site with directions and part numbers.

You may also want a transmission oil cooler if you don't already have one.
Some members who tow heavy loads will add airbags to the rear and even a weight distributing hitch.
 
First thing should be brakes.
Then a good weight distribution hitch, if you don't have one (one is required for 6500lbs).
Then a trans cooler, if you don't have one.

Next what is your gear ratio and budget.
If your budget is high your best improvement for towing power is changing to 4.56 gears and a gear vendor overdrive This will be easier on your trans, give you more power to the wheels and (if I remember correct) still give you a slightly lower solo cruising RPM then the 3.73 gears. The problem is, this isn't cheap and if you already have 4.10 gears probably not worth it. Or just do like CoveredAV said and trade up to a 2500.

It all depends on how much you want more power, how much you like your AV and how much you want to spend.

EDIT; You could also think about another vehicle for towing.
       How much would it cost to keep your wife's Nissan Armada?
        Insurance is cheaper on an extra vehicle.
 
Thanks guys but looks like I'm SOL!!  The budget is not an issue but the budget I want to spend on the Av is.  The plan was to just use it this coming summer and get a newer 1/2 ton either f150 or the new gen Sierra come fall.  I'm not sure what gears I have but I guess it doesn't matter since I won't change them anyhow.  I appreciate the advice and you likely saved me a couple bucks as now I will not bother doing anything.  I'll pound it this summer and then get rid of it.  Cheers
 
Your mind set is wrong going back to a 1/2 ton to tow 6500+ LBS.  You are better off with 3/4 ton truck.
 
I'll agree to disagree.  The new F150 either the 5.0 or ecoboost are beasts as i Know people who have both and you cant feel a trailer behind you and from what I hear the new 1500 Sierra is going to be quite nice.  Plus my armada is a 1/2 ton and pulls like a dream.  I'd agree if I was pushing 9000 or so I'd go with a 3/4 ton but 6-7000 a newer 1/2 ton is more than capable.  Anyhow I do have an external cooler on my Av (2003 155k miles) and the transmission was recently rebuilt at 150k so I don't foresee any problems in 1 summer's trips so I'll pound away.  I do like the truck unfortunately the drivetrain is just so weak.
 
For what axle ratio you have look in glove box at sticker for one of the following codes

GU5      Rear axle, 3.23 ratio
GU6      Rear axle, 3.42 ratio
GT4      Rear axle, 3.73 ratio
GT5      Rear axle, 4.10 ratio
 
PS600REVX said:
I'll agree to disagree.  The new F150 either the 5.0 or ecoboost are beasts as i Know people who have both and you cant feel a trailer behind you and from what I hear the new 1500 Sierra is going to be quite nice.  Plus my armada is a 1/2 ton and pulls like a dream.  I'd agree if I was pushing 9000 or so I'd go with a 3/4 ton but 6-7000 a newer 1/2 ton is more than capable.  Anyhow I do have an external cooler on my Av (2003 155k miles) and the transmission was recently rebuilt at 150k so I don't foresee any problems in 1 summer's trips so I'll pound away.  I do like the truck unfortunately the drivetrain is just so weak.
With my incident of 1/2 ton truck and travel trailer, I will never own a 1/2 ton any thing for towing.  (n)
 
ygmn said:
For what axle ratio you have look in glove box at sticker for one of the following codes

GU5      Rear axle, 3.23 ratio
GU6      Rear axle, 3.42 ratio
GT4       Rear axle, 3.73 ratio
GT5       Rear axle, 4.10 ratio
thaks for that info.  3.73s it is.
 
ygmn said:
For what axle ratio you have look in glove box at sticker for one of the following codes

GU5      Rear axle, 3.23 ratio
GU6      Rear axle, 3.42 ratio
GT4       Rear axle, 3.73 ratio
GT5       Rear axle, 4.10 ratio

I didnt think the regular Avy's came with the 4:10 ratio 2007 and above with the 5.3 litre?  Reading online they only have the 3 gear ratios.  I ordered my truck with the towing package on my LT, 4:10 wasnt an option, best I could do was the 3:73 to get 8100 lbs towing capacity
 
I mentioned in my reply to your other thread spidey that up until 2009 the AVs had a 5 speed transmission but from 2009 on they went to a 6 speed transmission and GM was going more for improving gas mileage not towing capacity. You are correct that 4.10 was not available in your 2011 year AV.
 
Vaeagleav said:
I mentioned in my reply to your other thread spidey that up until 2009 the AVs had a 5 speed transmission but from 2009 on they went to a 6 speed transmission and GM was going more for improving gas mileage not towing capacity. You are correct that 4.10 was not available in your 2011 year AV.

Thanks, and reading more, the maximum was also 3.42 ratio, thats what my truck has, not 3.73

Unless the Z71 have the 3 options.  I only have the LT, and the best gear ratio I could get with the tow package was 3.42

Im checking my RO codes tonight just our of curiosity
 
I have towed with a variety of 1/2 ton vehicles. The first thing I would suggest on your 03 is a brake upgrade. Getting the load moving and keeping it moving is the relatively easy part of towing but stopping is where you can find yourself wanting more stopping force than your vehicle can provide. I think the upgrade to 07 brakes is relatively cost friendly.
 
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