Towing

[dspoon]

Towing power does anyone have any suggestions on how to get more power and torque out of a 1999 slt 5.7 liter 4 wheel drive and still have good reliability.

[maxwedge]

Only a reprogramming upgrade to the pcm will help when it comes to increased torque needed for towing, changing diff gear ratios ( expensive job) is really the real issue with better towing power.

[dspoon]

Can you explain a little better in detail about the reprogramming? Is this something I can do or will I have to take it to a shop.

[YukonGMC]

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[YukonGMC]

http://www.gmfullsize.com/forum/showthread.php?t=42100

One of many tune threads. Lot of boy racers on these boards but they claim a PCM tune really brings the motor to life. $157. is cheap. Wonder what these tunes do to the engines in the long run ?

[bearinns08]

reprogramming the vehicle for more power in lower gears would help towing, i would think there wouldnt be too many problems in the long run as long as the final gear isn't messed with too much. not too sure though.

[dspoon]

What about a K&N filter kit and cat back exhaust system any luck with these mods or is it just a lot of extra expense and no gains. If so what kind of exhaust works best.

[Eggert]

Hi dspoon,
you plug the programmer into your ODBC (diagnostics) connector at the lower left edge of the dashboard, run the program, unplug it.
Just make sure that your chassis, brakes and tranny can take the trailer weight. You do have the aux engine oil cooler and tranny cooler?
The engine oil cooler is easy to retrofit, I did that on my 95 K1500.
Have a post on that, if you need more info. 2 hoses from the oil filter flange into the radiator.

In my case the K2500 chassis, brakes and tranny are the same for the 8.1 liter engine and the 6.0 liter engine.
It is rated for 12,000 lbs with the 8.1 liter engine, but with the smaller 6 liter engine it is rated for 10,000 lbs.

This is my post from another towing thread:

Here is my experience with a Yukon XL K2500, 6.0 liter engine towing a 10,000 lbs camping trailer:
I got a Hypertech programmer and recommend that. You can reprogram for more street or towing performance, with 87 or 91 Octane fuel. It also can firm up your transmission shifts.
I got the K+N cold air intake and took it off after 2 months, as the intake noise was getting to me.
I tried 2 aftermarket freeflow mufflers and reverted back to stock after 2 weeks, as the constant droning was hurting my ears. They sound great at the stoplight, for about 5 minutes. Then they get annoying.
Just my experience.

Update: The trailer weighs 10,800 lbs and I will keep the 6.0 liter engine with the 4.10 rear.
It tows fine, although I don't like 4,000 RPM on hills.
A Magnacharger would be nice, but not for $5,000.
Take care, Eggert

[vamc]

Summit racing has one as well. I live about 20 min from there