Chevy Duramax Engine Issues
Texas Diesel Company has the factory GM computer in-house! This allows us to quickly and effectively diagnose your vehicle saving you both time and money. We are also able to provide in-house programming of all components & modules installed in your vehicle, no different than the Chevrolet/GMC dealership would. If you’re another local shop interested in having us re-program a module for you, please call (903) 292-0400
Yes, we provide a 15-minute basic diagnosis for free! Keep in mind that this free diagnosis does not include us removing any parts from your vehicle for
further diagnosis. This service is limited to a visual check over as well as a quick look at your vehicles computer to determine where we need to start with diagnosis.
Unfortunately we do not, we usually draw the line at F-550/5500 vehicles. However, if you have something that you would like for us to work on please feel free to call us! We recommend using Big Daddy’s in Van Alstyne for semi and large trucks, their number is (903) 482-5600. They also provide 24 hour on the road service as well.
In most cases we prefer to go back with the OEM equipment (Ford, Dodge,
Chevy, etc.). Many of these components carry a 2-year unlimited mileage warranty as well. Although we aren’t able to get OEM parts for every repair, you have the option to choose aftermarket or OEM. Be sure to discuss this with your service writer at the time your vehicle is dropped off.
The Problem: You have oil or coolant in the valley of your truck
which presents itself down the back of the engine.
The Fix: The best way to fix this problem is none better than
removing the upper & lower intake and making a visual inspection. The best way to remove the upper intake is to loosen all the bolts that hold it down and try prying upward on them to get their fasteners out of the plastic. Most notably on the 4 bolts which attach at both of the intake manifolds to the valve covers. These are typically the ones which get hung up. Do your best to remove the passenger side first in a counterclockwise rotation. Typically you can pull the upper intake past the coolant by-pass, from there the intake should come out freely.
The Problem: In earlier model Ford Diesel Trucks, turbo failure
was a problem.
Why: These trucks have a Garrett G32 Turbo with ceramic ball
bearings. The reason most of these turbos failed is a result of the ceramic ball bearings in the turbo. Here’s the kicker, we’ve seen quite a few 2011 & 12 trucks with their original turbo and no issue. What’s their trick? REGULAR MAINTENANCE. Changing your oil every 5,000 miles and using good quality filters and oil will prevent this problem from happening in the future! Also keep in mind that these turbos have coolant running through them so keeping up with your coolant flushes and keeping your radiator clean is another way to keep your turbo in great shape!
The Problem: P04DB, P04E2, or P04E3 Or also know as a Crank
Case Vent Code
Why Did it Happen: The best scenario we’ve been able to come
up with is that the residual oil that sits in the crank case vent inlet
causes the sensor in the crank case vent to fail
The Fix: Simply order a new CCV vent from your local Ford
dealership. If your vehicle was built on or before Nov 11,2015 your vehicle may be covered under provisions of your New Vehicle Warranty from an extended coverage program. Call your local dealership to see if your vehicle is covered for free! If you are planning to pay for this repair out of pocket you’re probably looking at a $250-350 cost.
Turbo Shaft play is common among all diesel pickups, typically
those which haven’t had their oil changed regularly. Turbo shaft play is difficult to diagnose in writing and most technicians measure it by feel. You can measure turbo shaft play using a dial indicator, but most of the time it’s obvious when a turbo charger
is going out. Typically, the customer will state that they hear a funny whistling noise, lack of performance, or an awful noise coming from under the hood which is usually loud and high pitched. When checking for turbo shaft play, you will want to check for vertical & horizontal movement as well as thrust movement. If you see that the turbo blades have struck the walls of your turbo housing it’s definitely time to replace your turbo as this is too much play.
The Problem: On early 2011 model ford 6.7L engines, the glow
plugs have a tendency to break causing catastrophic engine
failure.
Why does this happen: The material used to make these glow
plugs is weakened over time and the tips break off
The Fix: Replacing these glow plugs with genuine OEM Ford glow
plugs is the best fix for this problem! The best way to go about
replacing these is by removing the fender wells
Transmission failure on dodge applications is very common. For
our customers, we highly recommend choosing a Revmax Transmission as your replacement. The best part about going with Revmax is their warranty! 2 year unlimited mileage on complete transmission assemblies & an out-of-warranty rebuild program with great cost-savings! Here are some of the common problems you’ll see when your transmission is on its way out:
o Won’t go into gear correctly o Coming in and out of gears at weird times o Skipping gears in the shift sequence o RPM spike before engaging into gear
Transmission failure on dodge applications is very common. For
our customers, we highly recommend choosing a Revmax Transmission as your replacement. The best part about going with Revmax is their warranty! 2 year unlimited mileage on complete transmission assemblies & an out-of-warranty rebuild program with great cost-savings! Here are some of the common problems you’ll see when your transmission is on its way out:
o Won’t go into gear correctly o Coming in and out of gears at weird times o Skipping gears in the shift sequence
o RPM spike before engaging into gear
Heater core failure is very common in all dodge models. The
problem usual presents itself in a few ways. o Leaking coolant onto passenger floorboard o Leaking coolant out of a/c condenser port (on firewall) o Lack of air flow when the heat is turned on, in this case your heater core is probably clogged up with debris since there is no filter on the a/c system
We wish we had better advice for you in this section but it’s a total toss up on what it might be! In most cases we find that TIPM (Totally integrated power module) is to blame but not all the time! Luckily, we have 3 different options when it comes to replacing your TIPM
o OEM replacement from dodge o Aftermarket Replacement o Having your original TIPM sent out and rebuilt
No start issues are extremely difficult to diagnose without some
bit of data. The best thing to do in this instance is to scan your truck and do some research into the codes it’s giving you. You may also need to look at some data points to determine what is actually causing the no start if you have multiple codes present. In most cases, on the LB7 engine, we see that injectors or fuel pressure plays a factor on the no start issues, we recommend looking at these data points first. Remember, just because your truck gives you a code for something doesn’t always mean that is the first thing you should replace. Always be justified in findings and have evidence and data to back up your theory before replacing any components.
Although we’ve never seen this one in our shop, its been noted online that its an issues on the LB7 Duramaxes. A quick diagnosis
of this issue will show nothing where the PRNDL should be. If your PRNDL is not displayed on your gauge cluster you may be able to suspect a bad Neutral Safety Backup Switch. This code may also be paired with P0708 (Transmission Range (TR) circuit performance)
Transmission failure on dodge applications is very common. For our customers, we highly recommend choosing a Revmax Transmission as your replacement. The best part about going with Revmax is their warranty! 2 year unlimited mileage on complete transmission assemblies & an out-of-warranty rebuild program with great cost-savings! Here are some of the common problems you’ll see when your transmission is on its way out:
o Won’t go into gear correctly o Coming in and out of gears at weird times o Skipping gears in the shift sequence o RPM spike before engaging into gear
We wish we had better advise for you in this section but it’s a total toss up on what it might be! In most cases we find that TIPM (Totally integrated power module, up to 2014-year model) is to blame but not all the time! Keep in mind, the TIPM with the most problems is 2014 and below. It’s very rare that a 2015+ will have a TIPM problem as there was a complete redesign. Luckily, we have 3 different options when it comes to replacing your TIPM
o OEM replacement from dodge o Aftermarket Replacement
o Having your original TIPM sent out and rebuilt
Heater core failure is very common in all dodge models. The
problem usual presents itself in a few ways. o Leaking coolant onto passenger floorboard o Leaking coolant out of a/c condenser port (on firewall) o Lack of air flow when the heat is turned on, in this case
your heater core is probably clogged up with debris since
there is no filter on the a/c system
This is an issue we see from time to time. In most cases we see that another shop has resealed the front timing cover and the customer still has a leak. In this case the carrier will need to be removed which resides behind the crank, cam, oil pump and CP3 gears. To complete this job the entire front of the truck needs to be removed and the cam needs to be removed. This is necessary as the carrier sits behind all of these components.
Like is predecessor the 6.0, Ford 6.4 Engines also exhibit oil cooler
failure. Although they look similar, the ford 6.4 oil cooler is slightly different then the 6.0, but both experience the same issues. When a 6.4 oil cooler fails, it allows oil to transfer into the cooling system. The reason the oil pushes over to the coolant system is due to the fact that the oil system runs between 15-45 psi while the cooling system has a maximum pressure of 16PSI (before the cap will start to release pressure).
The 6.4L Ford features a different injection system than the 6.0 &
7.3. The 6.4 utilizes a High Pressure Injection Pump, also known as HPIP. This pump creates a rail pressure of roughly 24,000 PSI at maximum capacity. This high pressure is needed to vaporize the diesel to allow it to combust in the cylinder. These pump tend to fail due to a built in regulator which controls the amount of fuel being pushed to the rails. Unlike newer CP4 pumps, this regulator cannot be changed thus causing the entire pump to be replaced when it fails. If you are experiencing sporadic rail pressure changes more than likely your regulator is failing. In a few cases we have seen that the fuel rail pressure sensors can be at fault more often we see that the pump itself is bad.
Blown head gaskets on the 6.4 are less common than the 6.0 but
we still see them from time to time. Aftermarket tuning, running the truck too hard, low coolant level are all factors to blame. Just like your Honda civic if you don’t keep the correct amount of coolant in the cooling system, the vehicle will overheat and it cause head gasket failure. The engines are designed to run at a certain temperature. As crazy as it sounds, we’ve seen head gaskets blow due to a small leak from a radiator. Over time that coolant continues to leak and eventually your vehicle doesn’t obtain the right amount of coolant to keep It below its desired operating temperature.
ON the LLY engine a no start could be many different things, but
the most common is that the fuel system needs to be primed. In normal operation, with no issues you shouldn’t ever have to prime this system unless a fuel filter has been replaced or the vehicle has run out of fuel. If you find yourself priming your system frequently, you may need to replace your fuel plunger assembly. In many cases we see that the rubber plunger inside the fuel filter housing is cracked or bad. Dorman makes a kit available to purchase from many major auto parts stores, but we have had little luck with these. Our recommendation is to head up to your local GM dealership and purchase a complete new housing assembly.
Water pump failure typically results from broken blades on the
water pump or shaft play that causes the front cover to wear so bad that the water pump cannot effectively move water through the cooling system. Bullet proof diesel has created far superior product vs OEM which features a billet aluminum wheel opposed to the plastic one from the factory.
High pressure oil leaks can be very difficult to find without the
proper tools and devices to identify leaks. The best way to identify high pressure oil leaks is to energize the system with shop air via the IPR port or the ICP port and listen for air leaks around the oil rail nipples, or at the stand pipes or dummy plugs. 9 times out of 10 we find leaks on the stand pipes. In some cases on the 05 and up models we’ve seen them leak at the T fitting on the back side of the high pressure oil pump. This pump, under WOT, creates around 3,000PSI of pressure so identifying these leaks is critical to the performance of your truck.
My 6.0 Powerstroke truck starts when it cold but not when its hot or after its been running for a while. This is something we see quite often, and its pretty simple to understand once you realize this; When oil is cold it is considerably thicker than when its
warm. This covers up some of the leaks in your high-pressure system as that thick oil can still create enough pressure to start your vehicle. Why does it still run after its warmed up? This is due to the IPR compensating for your leaks, your IPR will close off more than it should to make sure your truck will stay running after its been started. The reason your truck wont re-start after its warm is because the engine can’t turn over quick enough to create the 500PSI it need to begin firing the injectors. In a 6.0, your high pressure oil system needs at least 500PSI for the injectors to start firing.
IPR failure can cause many strange issues on the 6.0 motor. The
IPR controls the amount of pressure your high pressure oil system creates by opening and closing a valve on top of the high pressure oil pump. This valve regulates oil pressure by allowing some oil to bypass the oil rails or forcing more of the oil towards them. If your IPR isn’t operating properly it can cause drivability issues, no start issues, and lack of performance.
ICP failure on a 6.0 can cause your engine to also do many funny
things. Your ICP is reading actual pressure of the oil rail. The computer uses to ICP to determine if the IPR is doing it job correctly and to adjust for more of less pressure in your high- pressure oil system. Keep in mind that this does not read your low-pressure oil side it only reads the high-pressure side. A good way to check if this sensor is bad or not is to un-plug it and look inside of the ICP sensor itself. If you see oil present, its time to replace the sensor.
Another fact about your ICP sensor. It doesn’t need to be plugged in to run your truck. When the sensor is unplugged the computer will automatically assume that the high-pressure oil system is at its desired PSI. However, leaving this sensor unplugged will produce a check engine light.
Your low-pressure oil sensor sits on top of your oil cooler in the valley and is a single wire connector. Your truck doesn’t actually read how much low-pressure oil there is it only says if there is or is not pressure, this is why you won’t see your oil pressure gauge on your instrument cluster fluctuate with high RPM’s
Injector failure is somewhat common on the 6.0 and one of the
cheaper trucks to fix, at least when we’re talking about the price of the injectors alone. The nice part about 6.0 injectors is that
they’re easy to identify when ones are bad. By using our Ford IDS or a scanner which has a contribution or power balance test you can see how injectors are performing in real time. Injectors which exhibit +- 8 will need to be replaced soon. Injectors with greater then +- 20 need replacing immediately and are almost non- operational. Make sure to look at our FICM diagnosis before proceeding with injector replacement as your issue could lie here!
FICM issues are a huge problem with the 6.0 diesel engine. Your
FICM converts the trucks 12volt power into 48 volts which is what your injectors run on. If your FICM voltage KOEO (key on engine off) is less than 45 volts it’s time to replaced your FICM board. When the vehicle is running (KOER) and your FICM volts are less than 46.5 volts it’s also time to replace your FICM. In some instances, bad alternators and bad batteries can cause this issue as the FICM really needs a consistent 13.5 volts to operate properly. You’ll need a scan tool or reader which allows for data logging to see if your FICM is operating properly.
Unison ring failure is a very common problem in the 6.0 engine. What typically happens with the 6.0 is that the unison ring (the ring which opens and closes the veins in the turbo to allow for more of less boost) becomes caked with soot. Over time the unison ring will become stuck causing over boost issues (which can lead to blown head gaskets) or will waller out the hole which the VGT utilizes to open and close the ring. In most cases if this happens the ring will crack and you’ll be forced to replaced it with a new one.
We haven’t seen too many of these trucks in our shop yet as most of
them are still under factory warranty, but we know this much. Cummins decided to use the CP4.2 pump utilized on the GM and Ford platforms. Take a look at our CP4 disaster pages for more insight into why we believe this was a bad move for Cummins. Although the CP4.2 is a better design than the original we still much rather prefer the CP3’s more robust design!
This code is more common on 2011 and newer truck with the LML
and a CP4 injection pump but sometimes presents itself on older Duramax motors as well. We rarely see the CP3 pump fail but It can happen. Although we wouldn’t rule it out completely, it is an unlikely issue to see. We recommend changing your fuel filter and re-priming the fuel system. If this doesn’t fix your problem, a fuel rail relief valve, fuel pressure regulator or an external leak could be to blame.
Turbo failure on the LBZ Duramax is a common problem seen in
the 2006-2007 year model. We recommend taking a look at our write up for code P2563 to test your turbo in the LLY Section. If you’re hearing a whining or screeching noise we recommend that you immediately turn your truck off as potential damage could occur to your engine from debris coming apart in your turbocharger.
If your cruise control isn’t working then it may be time to replace your brake switch. You brake switch has 2 functions. Enable your brake lights, and tell the computer when your brakes are applied to turn cruise control off. If you have this code more than likely you’ll need to replace your brake switch.
1. Observe the Mass Air Flow (MAF) grams/second.
2. With the engine at a hot curb idle with the Exhaust Gas Recirculation (EGR)
valve off, expect 41 G/S. With the EGR valve on, expect 17 G/S.
3. If the G/S do not drop with the EGR on, check for a restricted EGR passage.
4. If the G/S are high both with EGR off and EGR on, inspect for a leak at theair filter or an incorrect air filter installed. The air filter is a calibrated restriction, and a leak or an incorrect filter will raise the G/S both with the EGR
If your truck has alerted you that you need to “Clean Exhaust
Filter” it means that your truck has not entered into regen mode in a while. This can sometimes equate to back pressure from the exhaust system, thus setting a mass air flow code because not enough air is able to enter the intake system. Your truck should be entering into regen mode on its own, if this is not the case then another issue may be at hand.
We recommend starting with a new fuel filter and re-priming your
fuel system. If this doesn’t work then inspect your fuel rail relief valve and ensure proper operation. If no issue is found there then look to your fuel pressure regulator. Although unlikely due to the CP3 robust design, you may need a new high pressure injection pump.
• Oil pan
o If you own a 7.3 you already know that they have a tendency to leak a little bit of oil. In the case of a leaking oil pan on a 7.3, in our opinion, there’s only one sure way to fix the leak. According to the Ford service manual the correct way to fix the leaking oil pan is to remove the engine from the truck, place it on an engine stand and flip it over to re-seal it. We’ve had our fair share of lessons when it comes to re-sealing these and we’ve tried everything imaginable to re-seal them in the truck, but it
hasn’t ever worked for us. If you plan on taking on this job yourself, we highly recommend grabbing an oil dipstick seal kit while you have the pan out (make sure to use OEM parts here). Furthermore, the block surface of the 7.3 DOES NOT adhere well with anything other than the Ford RTV designed for 7.3 engines. In fact, this has proven so well for us on the 7.3 that we use it in all sealing applications around the shop now. Lastly, use up every bit of the tube of sealant as it might not look pretty but it’s better than pulling your engine out again because you didn’t use enough. Make sure after you flip the engine over that you allow it to cure for a full 24 hours in an environment with a temperature above 55 degrees Fahrenheit.
• HPOP gasket leaking o This issue typically presents itself with oil in the valley of
your engine. Just because there is oil in the valley doesn’t mean this is your issue. The best way to identify this problem is by using a mirror and a flash light to see if the seal is leaking. This seal fits in between the high pressure oil pump and the back side of the front cover.
• Steel braided lines blown off o This problem is very easy to diagnose and it a very messy
one. These lines from the factory have proven to weaken around 200k+. These lines take the oil from the high pressure oil pump to each cylinder head. When one of these lines blow off your vehicle will turn off and you will see massive amounts of oil on the ground.
No start issues are extremely difficult to diagnose without some
bit of data. The best thing to do in this instance is to scan your truck and do some research into the codes it’s giving you. You may also need to look at some data points to determine what is actually causing the no start if you have multiple codes present. In most cases, on the LB7 engine, we see that injectors or fuel pressure plays a factor on the no start issues, we recommend looking at these data points first. Remember, just because your truck gives you a code for something doesn’t always mean that is the first thing you should replace. Always be justified in findings and have evidence and data to back up your theory before replacing any components.
Although we’ve never seen this one in our shop, its been noted online that its an issues on the LB7 Duramaxes. A quick diagnosis
of this issue will show nothing where the PRNDL should be. If your PRNDL is not displayed on your gauge cluster you may be able to suspect a bad Neutral Safety Backup Switch. This code may also be paired with P0708 (Transmission Range (TR) circuit performance)
