Performance upgrade

I have a 2004 Cadillac Escalade EXT 6.0 and want to get better performance from it. The motor is stock with 116,000 mi. I will be towing a 16 ft trailer with 2 touring motorcycles and accessories twice a year.
What are the best, cost efficient upgrades I can do for better performance and gas mileage?

Your Engine Control Module (ECM) will constantly adjust to bring all parameters within design limits. You can’t add anything that will do much. I suggest that you change the plugs and plug wires if it has not been done yet. Check the brakes to make sure you have enough pad left. When was the last time the transmission fluid was changed? That is due if it has not been done in the last 30,000 to 40,000 miles. Make sure you know the proper tire air pressure for towing and adjust as needed. Include the trailer, too.

Only thing that’ll make a significant difference is pressure - there have be supercharger setups for GM full size trucks and SUVs. But big $$.

With that rig, you are going to get 8-10 MPG, maybe 11 or 12 if you slow down to 50-55 mph…There is nothing you can do that will change that…Save your money…

“What are the best, cost efficient upgrades I can do for better performance and gas mileage?”

It’s a very limited menu.
Do you want more power, or do you want higher gas mileage?
You won’t be able to achieve both of these goals.

In fact, getting better gas mileage on something as big, heavy, and non-aerodynamic as this vehicle is well nigh impossible. However, if you are willing to spend big bucks on modifications, you can manage to boost the power output while simultaneously reducing the gas mileage.

Hopefully you won’t fall for the BS about inexpensive “performance chips” for the ECM.
Not only do they not provide any significant boost in power, but they can lead to engine damage.

Car makers today are very good at wringing every bit of performance and efficiency out of their vehicles, thanks to computer aided design.
Real improvement would call for upgrading every part of the system, front to back.
The next step up in this case IMHO would be a turbo diesel.
The sensible way to achieve that is another vehicle.

Short of bumping up the tire pressure there’s nothing you can do without spending thousands of dollars on forced induction and/or engine modifications.

Riding the bikes and leaving the excess baggage at home is an option as most touring bikes will easily get 40 MPG.

Some will disagree with me, but a small increase in both power and gas mileage is possible only if you’re willing to exceed exceed tailpipe emissions. Getting to that point will require reprogramming your car’s control module (at at minimum).

A quick Google search yielded this:

There are many handheld tuners available that will give you a little more HP and torque, allow you to firm up shifts, etc. I have one for my Mopar Hemi. The difference isn’t dramatic, but it is noticeable. Firming up shifts is probably desirable if you’re going to tow too, as it will help eliminate clutch wear. Obviously, use these at your own risk. If you stick to a preprogrammed tune, it’s relatively safe, but if you start tweaking parameters that you don’t understand, you can kill your engine pretty easily. Expect to spend at least $200-$300 for a tuner. Most also act as a scan tool and data logger, an added benefit.

If you’re going to tow with this, I’d strongly recommend getting a transmission cooler installed if your vehicle doesn’t have one. This is the number one upgrade to keep your transmission happy if towing.

You guys need to catch up with the times.

Go to, and look up your vehicle. This company has been putting out quality products for trucks, and should be able to help you. They deal with these sorts of issues all the time. Give them a call. Also, as another noted, make sure your tires are correctly inflated, and make sure your hitch is installed corectly and your trailer weight is properly distributed so you don’t end up with an ill-handling beast.

“You guys need to catch up with the times.”

Tuner boxes has already been mentioned. But the benefits of a tuner are going to be tiny, a few hp, maybe a mpg or two. Un-noticeable without a stopwatch, I’d bet. If a few tweaks of the computer was all it took for big hp/mpgs, why wouldn’t GM do this on their best selling, biggest profit line of vehicles?

And to do this without the benefit of a dyno would be even less worthwhile.

  1. on n/a gas engines, a custom tune or canned tune from a hand held tuner, isn’t going to do much on an otherwise stock engine. You might seem some gains if you have other mods and get a custom to maximize the gains from them.

  2. For the 2004 Escalade, for a noticeable gain, you’re going to have to go with forced induction. Hennessy makes or one time made both a supercharger kit and twin turbo kit for your application. IIRC those cost around $8k-$12k for the kit, not including the labor to install it or the necessary ECU tune.

Magnacharger still makes a supercharger kit for your vehicle, it cost around $6k for the kit, again not including labor.

  1. None of these things will increase fuel economy, the power gains with the supercharger or turbo setups can be impressive though.

Speed costs money, how fast do you want to go?

You want both more power AND fuel economy? Such things are only possible in the fantasy world of EPA tests. For example the Ford Ecoboost V6 has moe power and better EPA fuel economy than the standard V8, but in magazine road tests the V8 got slightly better fuel economy.
Why is this? Well the EPA test requires that you drive in a way that you never use the extra power of the turbo V6. You are not going to drive like that in real life.

Fodaddy “nailed” it on two key points:

  1. How much money you got?
  2. you cannot improve performance and gas mileage at the same time. More power comes from the burning of more gas. Of course, if you “gut” the interior and trunk (“wayback”?) and replace the hood with carbon fiber you might accelerate faster…but it won’t be a Caddy anymore.

GM has designed in the absolute optimum compromise between performance and mileage fo this vehicle. Improving pefo9rmance means finding a way to push more air and fuel into the engine and increasing its ability to breath out. Neither will be cheap. Either would cost fuel. Personally, I like the supercharger option…but hey, it’s your wallet!!

go for the turbos and the NOS. and report back how 15K got you more power that noone notices unless you are at a drag strip. at that point, wait…what’s the point? oh yeah, to make you feel better?

If the OP decides to go the expensive, but effective, route of turbocharging his engine, hopefully he will have enough money in reserve to overhaul that 9 year old transmission, which will not take kindly to the frequent heavy application of the gas pedal. My guess is that after a couple of months of full-throttle acceleration runs, his trans will bite the dust.

And, of course, it goes without saying that his gas mileage will become even lower as a result of the engine mods.

Again, I think he should start from scratch with a turbo diesel vehicle built from the ground up for towing.