Which Truck should I buy

[SidecarFlip]

The trick, if you will, to better fuel mileage is make the engine more efficient. Thats pretty easy actually by altering the fuel management parameters using an aftermarket tuner, more efficient turbocharger, free flowing exhaust or all the above.

Problem is, the newest Tier 4 compliant engines have very complex fuel management systems and everything has to be in synchronization or the engine derates, so modifying them will be moore costly and the Tier 4 engines don't have the longevity that a diesel is famous for. They run much hotter and heat kills, eventually.

The first cummins engines that went into Dodge pickups that had electronic fuel management had issues, mileage issues and still do I hear. Thats been improved on.

I still prefer the pre Tier 3 engines. They got good mileage and power was only limited by your wallet. My mildly modified 7.3 IDI Powerstroke puts 325 horses to the rear wheels at 55 mph in direct (overdrive locked out) and gets around 21 unladen and 15 pulling the gooseneck. I have a 1999 Freightliner conventional, short sleeper in the barn for hauling grain. It has a Caterpillar 1693TA with a 16 speed Road Ranger on 433's and it puts almost 900 horses to the ground and makes 1700 pounds feet of torque and it still gets 5+ mpg. Thats better than the newest Tier 4 on road diesels get with half that power.

The final problem with a new diesel pickup truck is there will be no backyard wrenching, ever. Maybe oil changes and coolant but thats about it. They are too complex for shadetree work. You have to be a computer technician to work on one. Same thing with the big engines.

 

[sp6x6]

I have 2 F350 7.3 's and I like them. But my buds with the mid 2000's durmax or Dodges kill me in mileage.My next work truck will be 2003-06 duramax.My buds with a towing business have 400,000 on there 7.3 Fords,3 trucks

 

[kbaerg]

I purchased a 2008 Chevy 2500 with the duramax (Isuzu) engine two years ago. The first three months I owned it I got 14-16 mpg highway. Then I put new exhaust, custom efi programming, and now I get 19-21 highway and pulling our 36' fifthwheel we get 14-15 (65mph). I am looking very closely at all makes for my next pickup as the wife and I want a 1 ton to pull our next fulltime camper. They better make some good changes. I like having the diesel for the power and torque for my needs.

 

[IdahoCTD]

Mike, I am a Chevrolet driver but have seen them all here around the ranch. The dodge diesels have now progressed to about 14 mpg.in the last year or two. I always thought the cummins was a great engine, and it is, or was. We just had to replace one that took a huge dump at just over 100 K, that was a $10 K + deal.

I would love to have a 2500 Durramax, but with the price of Diesel it need to give more mileage than gas.

So from what I have seen the used truck that will make me dig deep would be a 2003 Durramax. They ran very well and mileage was superb. I think they were the best of them.

If you run across one that is not completely worn out, you might want to give it a look. If I find one with low miles I will be looking hard.

Jeff

Jeff,

I wouldn't touch the 2001-2004 LB7 motor unless you want to spend some money on injectors or want to do a conversion to a LLY (2004.5-2005) or LBZ 2006-2007 motor. The injector design was one thing Isuzu messed up on. I build/sell hot rod parts for diesel trucks for a living so I have a pretty good idea which ones are the best. The LLY's have injector wiring harness issues and some had over heating issues. The LBZ's (2006-2007) and 2006 LLY's (the same motor just derated) were probably the best overall package. I have a 2008 LMM that makes 570hp to the ground how I drive it daily and have a race tune that is 640hp. It's been that way since 500 miles and now has 70k. My truck has never got that great of mileage though. BTW the 2006 and up trucks had 6 speed Allisons rather than 5 spd.

For Dodge's the best years are 2003-2007 5.9L with the 2003-2004 and the 2006-2007's probably getting the best mileage. 2006-2007 can be tuned with EFI Live and with a good tune can get some really good mileage as well as make some good hp. The down side to the Dodge's is the 4 speed auto tranny. If you build them they are tougher than a Allison and many of the top Duramax race trucks run Doge tranny's. The Allison uses adaptive learning (aka tap cells) to try and predict what the driver is going to do but with a high hp truck that means it tries to be too smart and burns itself up. The 2007.5 and up to 2012 Dodge's can get good mileage with everything deleted but the 6 spd 68rfe transmissions are junk. The aftermarket parts are getting better for them but they use the same shifting as a Allison.

I started into this a Dodge guy and still have a 2006. I do still think the 5.9L Cummins is the best motor for longevity out of all of them but they had some issues with dropping valve seats that didn't seem to be a specific year. All of the trucks need some things to help them out.

 

[Tikkamike]

Jeff,

I wouldn't touch the 2001-2004 LB7 motor unless you want to spend some money on injectors or want to do a conversion to a LLY (2004.5-2005) or LBZ 2006-2007 motor. The injector design was one thing Isuzu messed up on. I build/sell hot rod parts for diesel trucks for a living so I have a pretty good idea which ones are the best. The LLY's have injector wiring harness issues and some had over heating issues. The LBZ's (2006-2007) and 2006 LLY's (the same motor just derated) were probably the best overall package. I have a 2008 LMM that makes 570hp to the ground how I drive it daily and have a race tune that is 640hp. It's been that way since 500 miles and now has 70k. My truck has never got that great of mileage though. BTW the 2006 and up trucks had 6 speed Allisons rather than 5 spd.

For Dodge's the best years are 2003-2007 5.9L with the 2003-2004 and the 2006-2007's probably getting the best mileage. 2006-2007 can be tuned with EFI Live and with a good tune can get some really good mileage as well as make some good hp. The down side to the Dodge's is the 4 speed auto tranny. If you build them they are tougher than a Allison and many of the top Duramax race trucks run Doge tranny's. The Allison uses adaptive learning (aka tap cells) to try and predict what the driver is going to do but with a high hp truck that means it tries to be too smart and burns itself up. The 2007.5 and up to 2012 Dodge's can get good mileage with everything deleted but the 6 spd 68rfe transmissions are junk. The aftermarket parts are getting better for them but they use the same shifting as a Allison.

I started into this a Dodge guy and still have a 2006. I do still think the 5.9L Cummins is the best motor for longevity out of all of them but they had some issues with dropping valve seats that didn't seem to be a specific year. All of the trucks need some things to help them out.

Everyone is always talking about injector problems. Do the problems come back to people tuning them for performance? The reason I ask is my dad has several duramax trucks (more then any one person should have) 02 with 230k an 06 with over 100k had an 07 with over 100k till it burned in a shop fire, another 07 with less than 10k and my 2 company trucks which are an 08 top kick 5500 with 130k and an 09 3500 with 80k. ..now with all these we have never replaced a single injector. This puzzles me especially with the 02. It defys everything I have read people say about them. Any I site on that? I will more than likely be leaving Amy truck I get stock also.

 

[Broz]

IdahoCTD, Thanks for that advice. I just knew of a few 03's that got unbelievable mileage and had good power. I had heard they were the best years. But I trust your advice and will take it.

Thanks
Jeff

 

[SidecarFlip]

How soon we forget.....

Chevy/GM = Obama Motors, Taxpayer bailout, unpaid debt to taxpayers....

Dodge/Chrysler = Owned by Fiat, not an American company, profits go to Italy

Ford = Bailed thyemselves out, obligated to no one, good business sense. American owned and profits stay here.

While Ford has issues with their in house produced diesel, it's a domestically owned and operated company.

Only one choice far as I'm concerned.

My employer is 80% automotive, a first tier supplier of integral component materials so I know whats under the sheet metal and I know what the QC standards are.

In order of revelance in quality control First to last in domestic automotive....

Ford
GM
Chrysler/Fiat

Your choice, your money. I prefer to support the company the 'manned up' and went it alone, without Obama's help aka: your tax money.

Something to think about, at least I do.

 

[bigngreen]

Jeff,

I wouldn't touch the 2001-2004 LB7 motor unless you want to spend some money on injectors or want to do a conversion to a LLY (2004.5-2005) or LBZ 2006-2007 motor. The injector design was one thing Isuzu messed up on. I build/sell hot rod parts for diesel trucks for a living so I have a pretty good idea which ones are the best. The LLY's have injector wiring harness issues and some had over heating issues. The LBZ's (2006-2007) and 2006 LLY's (the same motor just derated) were probably the best overall package. I have a 2008 LMM that makes 570hp to the ground how I drive it daily and have a race tune that is 640hp. It's been that way since 500 miles and now has 70k. My truck has never got that great of mileage though. BTW the 2006 and up trucks had 6 speed Allisons rather than 5 spd.

For Dodge's the best years are 2003-2007 5.9L with the 2003-2004 and the 2006-2007's probably getting the best mileage. 2006-2007 can be tuned with EFI Live and with a good tune can get some really good mileage as well as make some good hp. The down side to the Dodge's is the 4 speed auto tranny. If you build them they are tougher than a Allison and many of the top Duramax race trucks run Doge tranny's. The Allison uses adaptive learning (aka tap cells) to try and predict what the driver is going to do but with a high hp truck that means it tries to be too smart and burns itself up. The 2007.5 and up to 2012 Dodge's can get good mileage with everything deleted but the 6 spd 68rfe transmissions are junk. The aftermarket parts are getting better for them but they use the same shifting as a Allison.

I started into this a Dodge guy and still have a 2006. I do still think the 5.9L Cummins is the best motor for longevity out of all of them but they had some issues with dropping valve seats that didn't seem to be a specific year. All of the trucks need some things to help them out.

Very good info! Making me feel good about my recent 07 Duramax purchase What do you recommend guys doing to tune up a Duramax to give it the best performance without going crazy. Chipping/tuning makes my stomach turn but it seems to work in trucks, my experience with it is in Ag tractors where chipping/tuning has been a parts and service opportunity!!

 

[IdahoCTD]

Mike,

There are exceptions to everything. I know of several high mileage LB7 motors (2001-2004) that have never been touched. I also know of many more that have gone through 2-3 sets of injectors. I actually have a friend that does quite well converting LB7's to LLY's or LBZ's because of the injector issues. In one of the high mileage trucks the owner runs a quart of ATF every other tank of fuel. I think a good additive definitely helps. The quality of diesel is pretty poor now days and since going to ultra low sulfur it seems injector failures are much more common. The newer injectors seem to handle the ultra low sulfur better though.

Nathan

 

[IdahoCTD]

Very good info! Making me feel good about my recent 07 Duramax purchase What do you recommend guys doing to tune up a Duramax to give it the best performance without going crazy. Chipping/tuning makes my stomach turn but it seems to work in trucks, my experience with it is in Ag tractors where chipping/tuning has been a parts and service opportunity!!

A good EFI Live tune will help the mileage and add some power. A stock Allison is quite tough but pushing much over 100hp extra will burn it up over time. The stock turbo won't cool over 100hp extra very well either. Also get a EGT gauge or a Edge CTS monitor to keep track of things. The monitor will also help trouble shoot things if you have a problem. I also highly recommend rerouting the crank case ventilation and blocking the EGR. The two make a nasty gritting paste in the intake parts that do nothing to help longevity. A used Duramax will have oil pool in the low spots of the intercooler and you'll see where the lower intercooler boots are oily because of it. That is the crank case ventilation being sucked through the turbo.

 

[SidecarFlip]

As an aside, we see injector issues across every make due to the fact that ULSD has no lubrication qualities. What occurs is the injector pintle galls and when that occurs, the spray pattern goes to hell or they stick and instead of spraying (the diesel must enter the combustion chamber as a mist for proper spontaneous ignition).

We recommend an aftermarket additive to increase the lubrication quality of the ULSD. I myself use the Caterpillar additive but any quality aftermarket additive works. Only takes a little, typically 1 ounce to 100 gallons. I've heard of owners adding 2 stroke oil or ATF to the fuel but I can't substantiate that as far as lubrication for the pintles. I can with the Cat additive and I believe JD also markets a fuel additive.

I said many posts back that the Isuzu built engine suffered from fuel stream filtration issues (which has been corrected). That was prior to ULSD.

Thank Obama and the 'green inititative for ethanol and ULSD diesel.

 

[SidecarFlip]

A good EFI Live tune will help the mileage and add some power. A stock Allison is quite tough but pushing much over 100hp extra will burn it up over time. The stock turbo won't cool over 100hp extra very well either. Also get a EGT gauge or a Edge CTS monitor to keep track of things. The monitor will also help trouble shoot things if you have a problem. I also highly recommend rerouting the crank case ventilation and blocking the EGR. The two make a nasty gritting paste in the intake parts that do nothing to help longevity. A used Duramax will have oil pool in the low spots of the intercooler and you'll see where the lower intercooler boots are oily because of it. That is the crank case ventilation being sucked through the turbo.[/QUOTE]

All well and good and something I did with mine right off (my 7.3 that is), but don't can the parts. Your truck won't pass an emissions test if your respective state enacts mandatory emissions testing. The way this country is heading, thats entriely possible.

Blowby mist is nothing compared to the EGR coking up the intake btw.

I'm a road draft tube person....lol

 

[IdahoCTD]

All well and good and something I did with mine right off (my 7.3 that is), but don't can the parts. Your truck won't pass an emissions test if your respective state enacts mandatory emissions testing. The way this country is heading, thats entriely possible.

Blowby mist is nothing compared to the EGR coking up the intake btw.

I'm a road draft tube person....lol

They'd never catch a EGR blocker plate for emissions on a Duramax. It's a thin plate that slips in between the up pipe and the EGR. You could even cut the tab off you use to hold it if a person was that worried about it.

Blow by mist combined with EGR makes a hell of a mess and is like a lapping paste in the intake system. Getting rid of both is the smartest thing to do. If you cut the plastic crank case vent tube and put some hose and a "T" in it can go back the way it was later. Pretty simple fix.

 

[SidecarFlip]

I suspect the scenario would play out much as the Class 8 scenario scenario is playing out. It's not a matter of sniffing the tailpipe for out of parameter emissions, in fact, thats old technology.

What is done now, is emissions testing officials plug into the molex connector that is on every engine management computer (all vehicles) and down load the snapshot data.

Every vehicle built in the last 10 years or so has the capability (some more,some less) to record in non-volitale memory, everything from sudden stops to hard acceleration and excessive side forces plus it records all engine and chassis events. It updates continuously and it's inside the ECM.

It's become SOP for insurance crash investigation as well.

You modify the engine and change the operating parameters, and it records the event. You install the plate you refer to and the ECM notes the change in parameters and records that event. Don't have to have a check engine light or fault code, it's recorded and all any officer has to do is plug in and down load.

In fleet safety, I have a program on this laptop that allows me to snapshot any of our trucks at any time to check for things like excessive speed, hard stops and excessive side forces and I can to that without plugging in, with a keystroke.

The transponder is coupled to the ECM. All I have to do is ask the transponder for the data and it's mine.

In my position as fleet safety officer, I need that, not to incriminate an employee, but to observe driving habits and take corrective action, if necessary.