Diesel Tech Questions
Dyno NumbersQUESTION: What is the best dyno to run my truck on for honest numbers? I want a good baseline to use when I add tunes and other parts to see how much they help.
ANSWER: What Diesel Power’s former staff editor Jason Sands said back in 2012 still stands true today:
“The lesson here is to not get hung up on the fact that your truck makes a few less (or a few more) horsepower than your buddy’s rig does when running it on a dyno. Even if you’re both testing on the same dyno, weather conditions can be different, the trucks may be driven differently on the rollers—even the temperature of the bearings for the rollers can change.
“If and when you do put your truck on a dyno, try and use a shop that deals with diesels. Diesel dyno shops won’t get freaked out by the smoke, and they should know how to properly load your truck. In the end, if you don’t like the results, you can always improve your truck’s power—or Photoshop the dyno sheet.” (Excerpt from Diesel Power article titled “Do Dynos Lie,” trucktrend.com/how-to/transmission-drivetrain/1205dp-do-dynos-lie/.)
And when you make performance upgrades, always use the same dyno and operator, do before and after runs, and see what direction the upgrades are taking your truck. To have an even better understanding of how your truck responds to changes, compare the gains shown by the roller numbers with before/after numbers at a dragstrip and on the open highway for fuel economy and driving traits. The key to determining how much improvement is made by any modification depends on keeping all the “testing” parameters as close to the same as you can: Repeat the conditions and driving style, fueling procedures, weather conditions (as much as possible), highway, and load as you did before the upgrades were done.
Body SwapQUESTION: I have an ’02 Ford Super Duty with a 7.3L Power Stroke engine. I was wondering whether anyone knows if you can put an ’08-to-’16) cab on a ’99-to-’03 F-250 or F-350 and if the instruments will work. The drivetrain on my old truck is all original and in great shape, but the cab and bed are rusting away. I haven’t been able to find much on the issue.
ANSWER: One of the recruiting slogans for the Ordnance Department of the U.S. Army in 1942 says, “The difficult we do immediately; the impossible takes a little longer.” Your body swap could easily fall into the latter part of the quote. Swapping the newer-style body on the older Ford chassis should be easy if both have the same wheelbase, body, and transmission style (automatic or manual). The real challenge is the wiring. Ford basically threw out the first-generation’s build book when it produced the subsequent second (’08 to ’10) and third-generation trucks (’11 to ’16).
As one of our body shop buddies remarked after swapping an even simpler ’03 Super Duty body onto an ’00 chassis for a customer experiencing the same rust issues: “There’s not a single nut, bolt, screw, wire, connector, tube, or hose that is the same. You’ll have to remove the radiator and core support while keeping the ECM and every wire and harness intact when removing the old body. The best way to handle the body swap is to lay all the old wiring over the engine and then drop the newer donor body into place. The newer body should readily mount on the rolling chassis if they are of like style and drivetrain. That’s the easy part. The fun begins when you basically gut the donor cab and reinstall all the plumbing (including HVAC) and wiring from the old cab and engine compartment.”
Nothing is directly interchangeable—not even the plug that goes to the dome light. It’s a very laborious swap that can easily take 80 to 100 hours for a shop that has experience with the project. You’ll also need to chat with your local DMV to see what hoops you have to go through to register a “late-model” truck that has an older engine under the hood. That could be the most difficult part of the entire effort.
Lost OverdriveQUESTION: The 47RE automatic transmission in my ’02 Dodge Ram is acting up. It jumps in and out of Overdrive with lots of gear hunting. It works fine when I slow down or jump on the throttle. It just doesn’t lock up once I get above 45 mph. Is there a way to wire in a toggle switch to force it to lock into Overdrive?
ANSWER: Are you sure the transmission is jumping gears? Or is it just unlocking and locking the torque converter? The answer depends on what it’s actually doing. Most 47RE lockup issues related to the converter locking/unlocking between 50 and 55 mph can be traced to “noise” interfering with the electronics that control the torque converter. The alternator is the culprit in most cases. The easiest method for determining whether the alternator is causing the interference is to disconnect the two-wire plug on the back of the alternator (when the symptoms occur) and drive the truck to see if the problem disappears. If the concern goes away, the rectifier in the alternator needs to be replaced or a noise filter needs to be wired into the converter circuit. Bad battery cables, poor grounds, and interference from other electronics, such as CB radios, can compound the problem.
On the other hand, if the transmission is actually jumping from OD to Drive, the list of possible causes expands considerably, ranging from being an issue with the throttle-valve cable to the governor-pressure transducer, or even a bad or out-of-adjustment throttle-position sensor. Tracking down which one is at fault requires a good ECM scanner and a good transmission technician.
Long-Term StorageQUESTION: My question has to do with storing a truck and recommended procedures when removing it from storage. I purchased a new Ram 2500 and was advised that I have to deploy to Japan. My father-in-law is going to watch the truck for me at his home in Wyoming. Prior to parking it, I topped off the DEF and fuel. I left another container of DEF as well. My father-in-law is starting the engine and adding fuel while I’m away. I think the best course of action upon my return is changing the fuel and oil filters prior to startup and then running the engine with a fuel additive. Is there anything else I should do or change in my plan before getting it back on the road?
ANSWER: Your very good question applies to many of our military readers deployed overseas. Mark Gotchall at Oregon Fuel Injection shared these tips for anyone storing a diesel-powered vehicle for several months or longer: 1) DEF has a shelf life. Make sure the fluid being added has an expiration date beyond the deployment timeframe. 2) Diesel with biofuel in it also has a limited shelf life (up to about six months). So, confirm there’s no biofuel in the vehicle prior to storage. 3) Change the oil and fuel filters prior to storage. 4) Don’t just start the pickup periodically. Instead, actually drive it for 30 to 45 minutes at highway speeds to allow everything to reach operating temperature. Starting and only idling the engine is worse than not starting it at all. A once-monthly drive should be fine. Mike Dunks at Dunks Performance also suggests hooking up a battery tender, such as Optima Batteries’ Digital 400 or Deltran Battery tender, to keep cells fresh during the long periods when the truck is parked.
Split-Shot SuggestionsQUESTION: My ’99 Ford F-250 has 260,000 miles, and I think it’s finally time to replace the injectors. The engine is totally stock, and I’d like to keep it that way, but a small boost in power would be nice because I do quite a bit of towing. A neighbor has a similar truck and says I should replace the original injectors with the newer single-shot versions. Will they make a significant difference in power and fuel mileage? Would anything else need to be changed to support different injectors?
via the Internet
via the Internet
ANSWER: By you’re saying the truck is totally stock, we assume you mean the factory-installed exhaust, air intake, and ECM tuning are all in place. If this is the case and you would like to keep it that way, then switching to the later-style, higher-flow single-shot injectors without other modifications, such as a custom tune, is impossible. Single-shot injectors operate as their name states: One single injection event occurs versus two. Single-shot injectors deliver more fuel with less oil pressure, and they are more efficient. But that doesn’t mean you can’t have the best of both worlds—or at least taste a little of the performance benefits offered by the later-style injectors while still running the split-shot squirters. Companies such as Swamp’s Diesel Performance offer split-shot units that flow more fuel than stock and thus make more power. The Swamp’s Stage 2 split-shot injectors for 7.3L Power Stroke engines are said to make 50 hp more than the stock injectors, using the original Ford ECM calibration—and as much as 175 hp with custom tuning.
“If you are hunting performance and it’s time for new injectors, then the decision to dive in and make the supporting upgrades to accommodate single-shot injectors has to be made,” says Kenneth Tripp at Tripp Trucks. “A minimum of custom tuning, exhaust, and intake modifications will get the cycle started. But if you want to keep your engine in its purely stock form, replace the split-shot injectors with a quality set of stock-replacement injectors and enjoy another 200,000-plus miles before thinking about them again.”
Shawn Smalley at Mobile Diesel Service also suggested doing such upgrades as installing a bigger compressor wheel in the turbocharger and installing a wastegate controller, along with a good high-pressure oil pump. Those little mods leave your engine “mostly” stock with the benefit of giving it an extra kick when called upon.
DEFQUESTION: I just purchased a ’17 Ford F-250. The salesman at the dealership was very helpful in taking the time to show me how everything worked, and along the way, he made it a point to mention I should only use Motorcraft’s DEF fluid or it could pose warranty problems related to the pollution-control system. Is that true?
via the Internet
via the Internet
ANSWER: No. The brand of DEF you use doesn’t impact a truck’s pollution-control system or its warranty coverage. As long as the DEF you purchase has a label showing it meets certification of the American Petroleum Institute (API) and International Organization of Standardization (ISO) 22241-1, it meets all the standards to use in any diesel pickup’s selective catalytic reduction (SCR) system. DEF is a necessary ingredient for the SCR to turn dangerous nitrogen oxides in the exhaust into harmless nitrogen and water. It does so by injecting DEF—which is made up of 32.5 percent urea and 67.5 percent deionized water—into the exhaust just as it reaches the diesel particulate filter. However, DEF has a shelf life. Typically, if DEF is stored at constant temperatures between 10 and 90 degrees and out of direct sunlight, it’s good for one year. The ideal storage temperature is around 77 degrees in a well-ventilated area. Like milk, there should be a date code or tag on the container showing the date the fluid was made (last six digits) and batch number. Some containers may also have an expiration or use-by sticker. The best advice is to buy the freshest batch of DEF on the shelf. By the way, DEF use is attributed to approximately 2 percent of the diesel fuel consumed.
EGR Scheduled ServiceQUESTION: Our company has a ’14 Ram 2500. The truck’s maintenance services are performed according to the schedule that is in the owner’s manual. At approximately 67,450 miles, the “Perform Service” warning came on, as the book says it will. I already knew this was going to happen, since I replaced the Closed Crankcase Ventilation filter myself, which the manual says is required at 67,500 miles, and found out how to clear the code. However, my service writer at our local dealership says that in addition to replacing the CCV, we must also do a $700 EGR/EGR-cooler cleaning. After trying to do some research on this, I can’t find anything conclusive about exactly what that service entails. Can you guys shed some light on this?
ANSWER: We read the ’14 Ram owner’s manual and couldn’t find any mention of a mandatory EGR/EGR-cooler cleaning required at 67,500 miles—or up through the 150,000 miles/120-month service schedule. The manual states: “Your vehicle will require emissions maintenance at a set interval. To help remind you when this maintenance is due, the Electronic Vehicle Information Center (EVIC) will display ‘Perform Service.’ When the ‘Perform Service’ message is displayed on the EVIC, it is necessary to have the emissions maintenance performed. Emissions maintenance may include replacing the Closed Crankcase Ventilation filter element.” Paying $700 for a service that isn’t required is a big outlaying of funds. However, it’s always good preventative maintenance to check the EGR valve to see if it’s just sooty, or if there is in fact a distinct crusty buildup on it. If it’s the latter, both the EGR valve and cooler should be removed and cleaned. Ram recommends using its special MOPAR EGR cleaner. We have found using Purple Power is a lot less expensive, and it does a good job cutting through the soot/carbon buildup. Just be sure you wash off the parts thoroughly with water before putting everything back together, because it’s a very strong cleaner. And for those who ask, no, the warranty on the smog-related equipment doesn’t cover cleaning, as that’s considered normal maintenance.
Boosting Baby DuramaxQUESTION: The diesel-performance bug has bitten me! I’ve owned a Chevrolet Colorado with the 2.8L “Baby Duramax” engine, and I use it as my commuter truck and to tow my side-by-side. It’s my first diesel pickup, and I love it. What can I do to take its performance to the next level?
ANSWER: Given the number of diesel performance-parts manufacturers that have embraced the 180hp 2.8L Duramax LWN, it appears the level of aftermarket upgrades for the I-4 engine could rival that of its 6.6L big brother. A quick Internet search shows a lot of choices from custom ECM tuning for engine and transmission performance to compound-turbocharger kits, as well as several air-intake, intercooler, and exhaust upgrades. To boost towing power, Duramaxtuner.com says its switch-on-the-fly programmer can add up to 52 hp and 80 lb-ft of torque, which is probably close to the limit of the little truck’s 6L50 six-speed automatic transmission. On the other end of the power spectrum, Screamin’ Diesel Performance offers a compound-turbo kit ($3,675) that is said to help the baby Duramax make up to 310 hp and more than 500 lb-ft of torque with mild tuning using EFILive (which also has shift-on-the-fly capabilities).