The engines in most cars and trucks are computer driven these days, but the installation of an engine tuner puts the driver in the driver’s seat instead. An engine tuner, or programmer, gives the driver the ability to fine tune the engine’s efficiency and performance by manipulating the computer’s input parameters to suit the driving task at hand.

Since 2007, we have lived year-round in a 14,100 lb, 36′ 2007 NuWa Hitchhiker fifth wheel trailer. For eight years, the truck we used to tow this big trailer was a 2007 Dodge Ram 3500 Single Rear Wheel Long Bed truck. Half of our miles driven, we towed the trailer. The other half, we drove it around town with nothing in tow and a few hundred pounds of cargo the bed of the truck. Once in a while we threw in an off-road adventure just for fun.

When the truck had 85,000 miles on it, we installed an Edge Diesel Evolution CS tuner, and what a world of difference that made to our driving experience, not only when we were towing but also when we were driving the truck around without the trailer attached.

In a nutshell, it has:

• Increased our truck’s power
• Improved our gas mileage
• Given us a readout for the transmission temperature.

And it was an easy installation to boot.

We also installed an optional companion product, the Edge EAS Exhaust Gas Temp sensor which gives us another piece of crucial temperature data when we are towing under heavy load. This is not a mandatory installation.

We couldn’t be more pleased with these upgrades!

This is a long post, and you can skip down the page to the following sections:

1. Why Install an Engine Tuner?
2. Edge Evolution CS Tuner – Tested and Validated
3. Installing the Edge Tuner
4. More POWER Driving in the Rocky Mountains
5. More TEMP DATA Towing in the Rockies
6. Better MPG – Fuel Efficiency Improvements, Towing and Not Towing
7. Additional Exhaust Gas Temperature Sensor Installation
8. Other features of the Edge Evolution CS tuner

1. Why Install an Engine Tuner?

We first became interested in the idea of installing the Edge Evolution CS tuner when Mark saw an article in the October 2014 issue of Diesel Power Magazine (“Tested, Proven, Validated — Edge’s DPF-On Tuner Walks the Walk”). This article discusses the improvements the tuner had made on our exact model truck (well, a 2009 rather than a 2007, but with everything else virtually the same, including the mileage!).

The Edge Diesel Evolution Tuner works on Ford, GM/Chevy and Dodge RAM.

Why install a tuner? It lets the driver fine tune the engine performance and boost power when needed

The beauty of the Edge programmer is that it doesn’t change anything in the engine permanently. It simply gives the driver the ability to fine tune the engine for its specific job at the moment, whether that is towing a big trailer, carrying a heavy load in the bed, racing off-road, or driving around town.

Light duty diesel trucks (i.e., Ford 250/350, Chevy 2500/3500 and Dodge RAM 2500/3500) are built for many uses, from towing heavy horse and RV trailers, to off-road racing, to driving across town and across country carrying big loads.

The on-board computer of every model truck is programmed at the factory to be able to do each of these things pretty well. However, it is impossible to program the computer to operate the engine at peak performance in all conditions. To make things worse, the truck manufacturers don’t provide the driver with a way to optimize the engine’s performance or to monitor some of the data the computer has already gathered.

Much of the truck computer’s capabilities and data remain inaccessible to the driver.

This is where the Edge tuner comes in, because it allows the driver to fine tune the engine for the immediate job at hand.

The idea behind the Edge tuner is to put the programming power into the hands of the driver, and to provide gauges for monitoring much of the data that the engine’s sensors detect. The Edge tuner can program the truck’s computer to maximize towing power or maximize non-towing fuel efficiency, depending on the kind of driving you are doing that day. It can also set the truck’s computer back to the stock factory settings, which is important if the truck is going into the shop for repair.

Because nothing mechanical is modified or tampered with, this means that nothing whatsoever is lost by installing the Edge tuner, but a whole lot is gained.

Why install a tuner? It gives the driver more detailed engine & transmission temperature data

We were intrigued by the Edge tuner because the installation appeared to be very easy, and the results were absolutely terrific. We tow our big fifth wheel trailer over huge, nasty mountain passes in the western states on a regular basis in the summertime, often tackling 10% and 15% grades on secondary roads. A little more towing power would be awesome!

What’s more, the tuner displays temperature data that the truck’s computer already has but that the truck manufacturer doesn’t display on the dashboard gauges. All this data is readily available via the OBD-II port (“On Board Diagnostic”) under the dashboard, you just have to plug into it. This is what the Edge programmer does — it is totally “plug-and-play.”

So, the Edge tuner would allow us to monitor the transmission temperature as we drove over mountain passes. This is vital data that is not accessible with our standard engine temp gauges.

Installing a companion product, the Edge Products EAS Exhaust Gas Temp sensor would let us monitor the exhaust gas temperature as well. Data from this optional sensor is shown in the middle gauge in the above image.

Having this extra information would allow us take action if something other than the engine coolant temperature overheated. It would also keep us better in touch with what was going on in the engine, in the event that the engine coolant temp was within an acceptable range but some other part of the truck’s propulsion were overheating. That scenario doesn’t seem possible, but read on…

You see, the factory installed engine coolant temp gauge in the truck cab tells only part of the story!

Why install a tuner? It improves the truck’s Fuel Efficiency (MPG)

We’ve always wished for a little better fuel mileage, both towing and when we are driving around town without our house attached. The tuner’s Level 2 programming mode promised improved fuel efficiency in non-towing conditions.

As it turned out, the tuner has increased our truck’s fuel efficiency in all situations.

What about the truck’s warranty?

A tuner (or “programmer”) does not permanently modify the truck’s computer or engine. There are “chips” on the market that make a permanent modification, but tuners and programmers don’t fall into that category.

We have called a few Dodge dealerships, and they have all assured us that if we had a truck that was in warranty (ours is not), they would service the truck even if it had an Edge tuner installed in it. Their recommendation to us was to reset the Edge tuner to “Stock” and then unplug it from the OBD-II port under the dashboard before bringing it in for service so they could properly analyze the engine (they use OBD-II port for their diagnostics).

The dealerships did say that if they found service was needed because of the presence of the Edge tuner (for instance, the tuner failed and shorted something out), they wouldn’t warranty that work, but they said the Edge tuner itself would not void any warranties.

 

 

2. Edge Diesel Evolution Tuner – Tested and Validated!

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It’s easy enough for manufacturers to offer a bunch of sales hype and fake claims about a product like this, but the aspect of the magazine article that really got our attention was that the folks at Diesel Power did a controlled experiment to measure both the horsepower and torque that this tuner generates. First, they put a stock 2009 Dodge RAM 3500 on a dynamometer and took horsepower and torque measurements. Then they installed the Edge tuner on the same truck, put it back on the dynomometer, and did the measurements a second time.

With the Edge tuner set to its lowest setting (Evolution Level 1), the results were:

	Stock (no tuner)	With Edge Tuner
Horsepower:	321 @ 2,900 rpm	362 @ 2,900 rpm
Torque:	605 ft-lb @ 2,350 rpm	711 ft-lb @ 2,300 rpm
Peak Exhaust Gas Temp:	1,266 degrees	1,200 degrees

So, they saw a jump of 41 hp, 106 ft-lb torque and a drop in peak exhaust gas temperatures. Wow!!

The Edge Tuner suddenly became a “must have” for us.

3. Installing the Edge Evolution CS Tuner

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The installation took a total of 90 minutes, from opening the box, to sitting down and reading the manual, to getting the unit installed in the truck. Very easy. In fact, it was so darned quick that Mark had completely finished the installation before I got my camera out to get pics of the unit going in.

The package contents include:

• The user manual
• The display unit
• A windshield mounting bracket
• Two wire/plug assemblies
• Tie wraps

You just mount the display unit on the windshield with the suction cup mounting bracket, plug the unit to the OBD-II port, use the tie wraps to dress it all up, and you’re done. So I guess I didn’t miss much!

 

4. More POWER!! Driving in the Rocky Mountains

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When we installed the Edge tuner on our truck, we just happened to be staying at the base of one of the biggest mountain passes we have ever traversed with our truck and trailer, the Million Dollar Highway that runs through the Colorado Rocky Mountains between Ouray, Silverton and Durango, on US Route 550.

This hair-raising, 70 mile stretch of road winds through dozens of 10 mph, 15 mph and 20 mph hairpin turns, going up and down grades that the Colorado Department of Transportation rates at “7% or more,” with some folks claiming a few are in the 9% range.

To add a little excitement to the drive, this is a fairly narrow two lane road with steep, unprotected drop-offs.

The views are divine, but it can be a white knuckle ride. The drive begins in Ouray at an altitude of 7,800′ and then climbs and descends over three major passes:

• Red Mountain Pass (11,018′)
• Molas Pass (10,970′)
• Coal Bank Pass (10,640′).

After finishing the Edge tuner installation, we took the truck up and down the first part of this road between Ouray and Red Mountain Pass about a dozen times. Mark set the tuner to Evolution Level 1, and he felt the difference in performance immediately.

He hit the gas pedal on a steep incline and his eyebrows shot up as he said to me, “This feels like a race truck!”

 

5. More TEMP DATA!! Towing in the Rockies

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Once he was comfortably familiar with the road and the mountain passes, and once we were ready to leave Ouray, we hitched the trailer to the truck and drove the entire Million Dollar Highway — Route 550 — over those three mountain passes from Ouray through Silverton to Durango.

Mark was impressed that the truck had plenty of power at all times and made it up and over the passes without straining. He kept the engine torque in its power band of 2,200 to 2,600 rpm, and he never had to depress the gas pedal all the way to the floor to maintain a safe speed.

You can set up the Edge tuner display to show whatever data interests you most.

On the CS model (which we installed), there are two large analog displays with accompanying digital readouts and a smaller digital display in between them.

The CTS model (which is slightly more expensive) has three analog displays with accompanying digital readouts.

Mark had set up our tuner to show the Engine Coolant Temp (ECT) and the Transmission Fluid Temp (TFT) on the two large semi-circular analog gauges to the left and right.

The ECT is a measure of the antifreeze temperature in the radiator, and is the “engine temperature” reading that is given in an analog gauge on the truck’s dashboard. It is also the temperature that most manufacturer’s use to indicate that the engine has overheated, usually displaying a big red light on the dash.

The TFT is a measure of the transmission fluid temp, and it is not a value that is tied into any of the dashboard instrumentation on most trucks.

In general, both the ECT and TFT temps should be kept below 225 degrees, although newer trucks can run slightly hotter than older trucks.

The digital readouts on the Edge tuner display unit are big numbers that are easy for both the driver (and passenger) to read.

Getting into the Red Zone

What a shock it was to begin our first big ascent on Red Mountain Pass and to see that while the Engine Coolant Temp was in the normal range, according to both the factory-installed in-dash gauge and the Edge tuner (which showed 215 degrees), the Transmission Fluid Temp went into the red zone, climbing past the safe zone of 225 degrees up to 237 degrees.

The ascent was almost over when we hit this max, and both temps quickly dropped back down as we descended towards Silverton. The ECT cooled down to 198 degrees and the TFT cooled way down to 163 degrees.

On the next ascent, Molas Pass, (10,970′), the Engine Coolant Temp climbed back up to 215 degrees (still in the safe zone) while the Transmission Fluid Temp topped out at 244 degrees.

In the next valley, the temps dropped back down again, and on the last ascent, Coal Bank Pass (10,640′), the temps climbed again, but this time the Transmission Fluid Temp stayed below 235 degrees.

Insights

We were both amazed that the truck never overheated, according to the dashboard Engine Temp gauge, but in fact, the transmission had exceeded its limits by as much as 19 degrees, or 8%. We never would have known that without the Edge tuner, and it made us wonder just how hot the transmission fluid would be in the event that the engine coolant temp actually went into red alert.

If the transmission stays over 225 degrees for too many minutes, the transmission fluid breaks down permanently, and the transmission can be irreparably damaged.

You can set up alerts in the Edge tuner display so that buzzers sound and/or the display flashes when any of the data being monitored exceeds its maximum. However, by default, the alert system is turned off. This makes sense, as it could be annoying to have a buzzer going when you are already nervously looking for a way to safely pull over to let the engine cool.

For anyone installing the Edge tuner, just keep the magic number 225 in mind, and you will easily see when you have exceeded that value on the tuner’s display, as the numbers are nice and large. There is also a “red zone” on the analog display, but we found it was so faint that we did not notice it until we studied our photos of the gauge afterwards!

 

6. Better MPG – Fuel Efficiency Improvements

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When we tow, we set the Edge tuner to Level 1.
When we are not towing, we set the Edge tuner to Level 2.

Increased MPG – Towing – Improves by 2 MPG!

Before we installed the Edge tuner, we typically got somewhere between 9.7 and 10.5 mpg while towing for long distances, according to the electronic gauge in the truck. This gauge has its limitations, because it is somehow averaging the most recent miles driven, but I have not been able to find exactly how the average is calculated or how many miles back it goes — is it the most recent 100 miles? 500? 1,000?

Measuring the MPG from one full tank of diesel to the next is a more accurate method, but it is still fallible because one tank may be filled slightly more than another, and if the tank of gas includes both towing and non-towing miles, then the numbers are thrown off.

So, I can’t offer scientifically collected numbers here, but I can say that after we installed the Edge tuner, the gauge in our truck now typically shows numbers between 11.7 and 12.5 when we are towing consistently for distances of 250 miles or more.

In essence, the truck is saving 2 miles per gallon while producing more power. Very impressive!

Increased MPG – Not Towing – Improves by 3 MPG!

Our truck always used to get somewhere in the 16-18 MPG range when we weren’t towing, better on highways and less in town.

Now, if we travel 100 miles or more without the trailer, we see an MPG in the 19-21 range. That is an improvement of 3 MPG!

What a shock it was the first time we drove 130 highway miles at 65 mph and saw 21.6 MPG on our truck’s mileage gauge!!

Return on Investment

If this fuel savings alone were used to justify the cost of a new Edge Evolution tuner, how many miles would we have to drive for the unit to pay for itself?

If we assume the tuner costs ~$450 and diesel costs ~$3/gallon (both rough but reasonable estimates given prices in the last year), and we assume a conservative savings of 2 MPG, whether towing or not, and we tow for half the total miles driven, we will have saved approximately $450 in fuel once we have driven about 15,500 miles.

Of course, the tuner does a lot more than save a little fuel…

 

7. Additional Exhaust Gas Temperature Sensor Installation

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A month after installing the Edge Evolution CS tuner, Mark installed a companion product, the Expandable Accessory System (EAS – product #98603) Exhaust Gas Temperature sensor. This product measures the temperature of the exhaust gases in the exhaust manifold, giving the driver yet more insight — beyond just the antifreeze temp and the transmission fluid temp — into how hot the engine is running.

This was an optional installation, but after seeing the value of knowing the transmission fluid temperature, we wanted to be able to monitor our exhaust gas temperature readings as well.

This installation was quite a bit more complicated than the Edge programmer, as the probe had to be inserted into the exhaust manifold. This required drilling a hole in the exhaust manifold, tapping the hole, screwing the probe into the newly tapped hole, and running the wires through the engine firewall back to the Edge Evolution tuner where they plugged into the back of the display unit.

The hardest part of this installation was drilling and tapping the hole, in part because the exhaust manifold is not super easy access to with a large drill, and in part because the metal of the exhuast manifold is very thick and hard.

The instructions in the manual called for:

• 1/8″ drill bit (or similar size) for a pilot hole
• 21/64″ cobalt drill bit (or less optimally a 5/16″ drill bit) for the probe hole
• 9/16″ wrench or socket
• 5/8″ open end wrench
• 1/8″-27 NPT thread tap (make sure you have a long tap handle for lots of leverage)
• Permatex Anti-Seize Lubricant
• Phillips screwdriver
• 5/16″ or 8mm wrench

The most important thing is that the tap handle be big and solid to give you lots of leverage, because the solid cast iron on the exhaust manifold is very thick and very hard. This will make the difference between an easy installation and a miserably hard one.

As always, Mark got the project underway before I got my camera going, so I don’t have a “before” photo. However, the “after” photo below shows what you’re gunning for and what stands in the way between you and the exhaust manifold.

First, unscrew the bolt holding the two black tubes in place so they can be pushed aside.

The probe will be inserted here.

Space is tight, so a 90 degree right angle drill is necessary. Drill a pilot hole first. Then drill the real hole for the probe.

In order to avoid getting metal filings in the wrong places, grease the drill bit first. Drill a little, then wipe the drill bit down, re-grease it, and drill a little further. Do this for both the pilot hole and the real hole.

Now the hole is ready to be tapped. Grease or oil the tapping tool well, and work it in and out a quarter turn at a time. As before, after a few turns, back it all the way out and wipe off the metal filings, and re-grease it.

As mentioned above, a small tap handle will not give you enough leverage for the thick, hard cast iron of the exhaust manifold.

Once the hole is drilled and tapped, the probe can be screwed in. Grease the probe’s threads with <strong>Permatex Anti-Seize Lubricant first. Then, a cable connecting the probe to the Edge tuner is run from the exhaust manifold back through the engine firewall between the engine and the cab, and on up to the tuner.

 

Mark opted to put the display for the exhaust gas temperatures in the middle display area between the Engine Coolant Temp and the Transmission Fluid Temp. Of course, you can choose to display any data in any of the three display areas, and Mark experimented a little before settling on ECT on the left, EGT in the middle and TFT on the right.

The more expensive Edge Evolution CTS tuner has three large displays with both analog and digital readouts rather than the two large displays and one small one on the Edge Evolution CS tuner.

Results

We installed the Exhaust Gas Temperature probe after we had done all of our mountain driving for the season, so we have yet to test it in the mountains. The “overtemp” magic number for the EGT is 1350. Typical temps we have seen driving around town are in the mid-900’s, and climbing a long 5% grade while towing our fifth wheel, we’ve seen the mid-1100’s. However, these have just been the long, gradual grades of Arizona and not the steep switchbacks typical of Rocky Mountain passes.

We will report our findings about the exhaust gas temperature readings once we have taken our RV over a big mountain pass!

 

8. Other Features of the Edge Tuner

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The Edge tuner has a ton of other things it can do, because it essentially opens up the truck’s computer so the driver can access the data and temporarily modify the input parameters for the current driving conditions. (Obviosuly, you must be parked to mess with the menus on the tuner.)

Our only interest in the tuner has been the improved power while towing, improved fuel economy while not towing and the additional temperature data that is made available when towing over big mountain passes.

Maintenance and Diagnostic Trouble Codes

There is a Maintenance Manager mode where you can establish a reminder system for standard maintenance items like changing the transmission fluid, checking the trans case fluid level, inspecting the brake pads, lubing the tie rod ends and rotating the tires. Simply get it started with your current odometer reading, and the reminders will alert you at your chosen intervals.

If you are really concerned about fuel economy, there is a Mileage Coach that can show you how to vary your foot’s pressure on the gas pedal to maximize fuel economy as you drive. You can also find out the fuel cost per mile of a particular trip if you enter the price of the fuel you buy!

In addition, the Edge tuner can reveal the Diagnostic Trouble Codes that are present when the truck’s Check Engine light goes on. Most codes can be looked up on the internet, so this might save some head scratching before heading off to a mechanic to get the problem looked at.

For racers

We have used only Levels 1 and 2 (for towing and around town driving), however there are two more levels beyond that for increased power performance, if you find your truck on the starting line of a racecourse. These modes adjust the fuel injection and timing to be more aggressive. In addition, the CTS model can be interfaced to a backup camera and it can also monitor the pitch, roll and G-forces!! For those with racing in mind who find themselves at a drag strip, there are also 0 to 60 mph performance tests and quarter mile tests, and the record highest values of these tests are maintained.

Studying the Data

You can also connect the Edge tuner to a computer using the USB port. You can retrieve all the data from the Edge programmer into an Excel-readable .csv file. using the downloadable Windows software called MyStyle (instructions given in the manual).

For us, however, we are content with just the basics!

Product info:

• Edge Diesel Evolution CS Tuner – The model we installed
• Edge Diesel Evolution CTS Tuner – A slightly more sophisticated model with 3 analog gauges instead of 2
• Companion Edge EAS Exhaust Gas Temperature Sensor – An additional sensor for obtaining Exhaust Gas Temp readings
• Edge Product Lineup Explained – Which models do what?!
• Edge Products Website – Scroll down to the lowest left corner to see a Very Cool Video called “Proving Grounds”

For fun:

• Driving Colorado’s Million Dollar Highway  – Take your eyes off the tuner to see some gorgeous scenery
• Ouray Corado – A great area to visit with your RV!

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