who makes the best diesel truck?

[Peacock]

The injector failures the LMM have been seeing are hardly called reliable. The 6.7L is having some programming issues and EGR/VGT issues, again, due to programming.

The 6.4L is a waste of time and money. I don't think the new "Scorpion" diesel will be much better.

At this point you're better off to wait a year or two til the bugs are worked out to buy any diesel truck.

I'm just going off the dealer group I work for. We own dealers for the 3 makes. The LMM D-Max trucks have been rock solid for us in this area.

Maybe we are an anomoly. We've had a bunch of bad CR 5.9 injectors and even replaced a few motors. We've probably replaced a dozen or more turbo's on the 6.7l motors and an injector or 2. Had one with a bad PCM that clogged the DPF because it refused to do a regen.

 

[cashishift]

The LMM D-Max may be the most reliable of the current 3.

The 6.4 Ford doens't seem much better than the 6.0.

The 6.7l isn't a bad engine at all, just got some teething problems with the EGR system and how it effects the VGT.

What basis says the LMM is the most reliable?

Based on the research I've been doing.. LBZ - EGR = winner.

 

[cashishift]

I'm just going off the dealer group I work for. We own dealers for the 3 makes. The LMM D-Max trucks have been rock solid for us in this area.

Maybe we are an anomoly. We've had a bunch of bad CR 5.9 injectors and even replaced a few motors. We've probably replaced a dozen or more turbo's on the 6.7l motors and an injector or 2. Had one with a bad PCM that clogged the DPF because it refused to do a regen.

the DPF is such a joke..

there isn't a single truck out there that is getting good mileage with one on it.

just a stab in the foot of diesel, diesel power has such potential in cars and trucks.. just gotta get past that stigma!

 

[Peacock]

What basis says the LMM is the most reliable?

Based on the research I've been doing.. LBZ - EGR = winner.

I'm only comparing the current engines. Not the old pre-EGR models.

 

[cashishift]

I'm only comparing the current engines. Not the old pre-EGR models.

The LBZ has EGR, so does the LLY.

the only one as far as i know the LB7 didn't have it.

The LMM has both the DPF and EGR..

All of these motors are basically the same, just with different stuff on them for emissions and different tune.. the LLY is a detuned LBZ.. the LMM is a LBZ with the DPF stuff on it..

basically the same all across the board.

 

[djmercer1]

The injector failures the LMM have been seeing are hardly called reliable. The 6.7L is having some programming issues and EGR/VGT issues, again, due to programming.

The 6.4L is a waste of time and money. I don't think the new "Scorpion" diesel will be much better.

At this point you're better off to wait a year or two til the bugs are worked out to buy any diesel truck.

its not the lmm with injector troubles, it was the lb7, and it was backed by gm with a 200k milespecial service policy....

the only issue with the lmm/lbz(mechanically the same, lmm has more emission crap) is cracked pistons when powered up through tuning...

 

[djmercer1]

The LBZ has EGR, so does the LLY.

the only one as far as i know the LB7 didn't have it.

The LMM has both the DPF and EGR..

All of these motors are basically the same, just with different stuff on them for emissions and different tune.. the LLY is a detuned LBZ.. the LMM is a LBZ with the DPF stuff on it..

basically the same all across the board.

not totally true...

lb7 and pre2006 lly are mechanically similar. exception are injectors are outside the valve cover, and the lly had the variable vane turbo, lb7 was fixed vane with wastegate....

2006 lly and lbz are identical except for tuning. lmm and lbz are nearly the same ecept for emissions and tuning....

2006 lly forward has the allison 6speed tranny with tap-shift. there are some rummors of the 06 lly with the 5speed ally..... the only lb7 with pcv/egr was the cali model. all lly/lbz had pcv and egr. lmm has egr/pcv and dpf...

 

[cashishift]

its not the lmm with injector troubles, it was the lb7, and it was backed by gm with a 200k milespecial service policy....

the only issue with the lmm/lbz(mechanically the same, lmm has more emission crap) is cracked pistons when powered up through tuning...

and with the LMM.. dpf regen fuel mileage is just terrible.. 8mpg

All these extra emissions put on diesels, sure isn't doing anything to help their cause.

so much power and effiency available.. yet no one even bothers to look.

 

[cashishift]

not totally true...

lb7 and pre2006 lly are mechanically similar. exception are injectors are outside the valve cover, and the lly had the variable vane turbo, lb7 was fixed vane with wastegate....

2006 lly and lbz are identical except for tuning. lmm and lbz are nearly the same ecept for emissions and tuning....

2006 lly forward has the allison 6speed tranny with tap-shift. there are some rummors of the 06 lly with the 5speed ally..... the only lb7 with pcv/egr was the cali model. all lly/lbz had pcv and egr. lmm has egr/pcv and dpf...

close enough for government work

 

[djmercer1]

and with the LMM.. dpf regen fuel mileage is just terrible.. 8mpg

All these extra emissions put on diesels, sure isn't doing anything to help their cause.

so much power and effiency available.. yet no one even bothers to look.

your right about the mileage..... dads lmm gets about 18l/100km unloaded, my lly does about 12.5l/100km driving the same routes, when hauling it does go down somewhat, the old lb7 i had was even better than my lly. the regen on the lmm reportedly consumes upwards for 3 gal of diesel every 500miles.....

we need to get rid of the emissions crap, if my milagegoes down by 20% due to emissions, i then doing more harm than i would have if i had blew a little soot. my memory tells me that the lb7 wasnt blowing piles of black smoke anyway....

 

[motoroilmccall]

its not the lmm with injector troubles, it was the lb7, and it was backed by gm with a 200k milespecial service policy....

the only issue with the lmm/lbz(mechanically the same, lmm has more emission crap) is cracked pistons when powered up through tuning...

IDK where you are, but the LMM most certainly IS having injector failures out here. Between nozzles cracking and o-rings leaking the things are smoke machines that barely move once in limp mode.

I'm not bashing Chevy, they are without doubt the second best diesel out there, but Cummins has the track record, the engineers, and the money that GM doesn't, and they do make the best diesel out there in more than just the light truck segment.

The argument has been brought up religiously, the Cummins is medium duty, the Duramax is still a light duty. Ignore it all you want, but to diesel truck drivers, size matters...

 

[djmercer1]

IDK where you are, but the LMM most certainly IS having injector failures out here. Between nozzles cracking and o-rings leaking the things are smoke machines that barely move once in limp mode.

I'm not bashing Chevy, they are without doubt the second best diesel out there, but Cummins has the track record, the engineers, and the money that GM doesn't, and they do make the best diesel out there in more than just the light truck segment.

The argument has been brought up religiously, the Cummins is medium duty, the Duramax is still a light duty. Ignore it all you want, but to diesel truck drivers, size matters...

well, according to the gm service system, theres been less than 400 injector jobs on lmm/lbx in canada and the us combined, covering 2.5 years. there were some injector like issues related to wiring for both lly and lmm, but not the actual injectors.

ill admit the cummins 5.9 is a very good power plant, the jurys still out on the 6.7 though, its unfortunate that the dodge truck wasnt a better package worthy of either... although the new asin tranny seems to be very good...

the lmm/lbz has only been in production for 2.5 yrs, the lb7 for 4 yrs and lly for 2 yrs, it took much longer to get the bugs worked out of the cummins than either production run, the cummins in had a full 5yrs as a production motor before being put in the dodge as a competitor to the 6.2l detroit and 7.3l international....

 

[046]

call it what you want... but cummins powered trucks of any flavor are highly desired by folks that haul a load.

take a peek at Ford and Chevy diesel truck forums. even on their own turf, cummins gets mentioned with grudging respect.

don't get me wrong... cummins has their own problems like everyone else. look at all the VP44 (fuel pump) failures on 24valve cummins. which are solved with FASS pumps and fuel pressure gauges. stories of transmission failures abound... mismatch for cummins' output.

overall cummins has less issues than everyone else. older 12valve basically had no weakness once the killer dowel pin was fixed. it's a fact that much older first gen 12v (pre 94) get better mileage... hauls huge loads... all without complaint ... equal to much newer trucks.

small wonder why cummins powered trucks tend to have the best resale values too.

 

[Bearcreek]

:agree2: You'll never see a powerstroke or duramax swapped into a Dodge. Cummins swaps into Fords and Chevy's are common.

 

[motoroilmccall]

well, according to the gm service system, theres been less than 400 injector jobs on lmm/lbx in canada and the us combined, covering 2.5 years. there were some injector like issues related to wiring for both lly and lmm, but not the actual injectors.

ill admit the cummins 5.9 is a very good power plant, the jurys still out on the 6.7 though, its unfortunate that the dodge truck wasnt a better package worthy of either... although the new asin tranny seems to be very good...

the lmm/lbz has only been in production for 2.5 yrs, the lb7 for 4 yrs and lly for 2 yrs, it took much longer to get the bugs worked out of the cummins than either production run, the cummins in had a full 5yrs as a production motor before being put in the dodge as a competitor to the 6.2l detroit and 7.3l international....

The first gen VE Cummins trucks debuted in 89 due to lack of engines. The 6BT had been out for a number of years before it made it into the Dodge. Mostly it was an Ag engine used in tractors and skidders and other various heavy equipment. Obviously those applications abuse the powertrains much worse than any OTR application. It wasn't a matter of getting the bugs worked out at all, in fact it was nearly perfect when it debuted in Case equipment. The only real problem was a crappy oil filter system that would have been fine on OTR applications, but couldn't keep up with the dirty conditions off-road.

If the 5.9L motor was a great powerplant, how can the 6.7L not be? Its practically the same motor with a slightly larger bore, and a DPF and EGR system. And I don't know how you can even compare the 6BT to a 6.2L Detroit motor that was a joke then, and makes GM guys puke a little when you bring it up now.

The 7.3 was always a reliable motor, but it was never a powerhouse until 97 when it was turbo'd, intercooled, and direct injected.

The Dodge is a great truck, it has been since the First Gen. I'll openly admit that until 04 the Dodge Auto's were basically junk if they weren't properly built. But unlike the General, and Ford, Dodge offered, and still does offer, a MANUAL transmission, which is what every diesel should be equipped with for hauling anything. The other big advantage that Dodge, and even Ford have over GM is a real truck front end. IFS is a joke, and I'm clearly not the only one who thinks so.

I'll say this, and I've said it before. Ford has hands down the best chassis. From a super strong frame, to a radius arm front solid axle, to proven reliable Dana axles. I personally don't like the exterior styling, but it works for some people.

Dodge has the best engine, no question... Its why Ford and GM guys pull their original diesel engine to swap it for a Cummins. The Aisin automatic (which FYI is available only on C+C models) is also the best built trans out there, its a medium duty unit, unlike the light duty Allison, 68RFE, or Torqshift, and it weighs a ton. The 68RFE has also shown to be an incredibly reliable transmission so far, even with aftermarket upgrades. I personally like the Dodge styling and new 2010 interior the most as well, although the Ford interior is very impressive. The AAM axles are excellent, but I worked for Dana for years, so I've seen the limits of both (I was a test technician first at the TRP plant in Ottawa Lake, MI, then the ASG plant in Maumee, OH).

The Chevy has a nice motor, and an excellent transmission. I'd take the Allison over anything but the Aisin, and if I was gonna really hot-rod one of these trucks, the Allison would be my choice because of its aftermarket support (although at the extremes the clutch-clutch shifting of the Allison is a huge problem, and most guys swap to the 47RH of the 12V Cummins trucks, even the Aisin can't handle it). The rest of the Chevy doesn't impress me... The frame hangs low, the front end isn't suitable for hard work (like logging, farming, or hard off-road use), the interior looks like it was pulled out of an Impala, and the body is way too big for those tiny wheels and tires.

Most of this is my opinion, and you aren't going to change that. However my opinion is based on what I know, and how I use trucks. Each of these trucks have strong suits, and shine in their own application. Then again, the Ford shine's on the outside, but the motor is one of those things where I'll say to the end, you can polish a turd all you want... Its still a turd.

 

[djmercer1]

The first gen VE Cummins trucks debuted in 89 due to lack of engines. The 6BT had been out for a number of years before it made it into the Dodge. Mostly it was an Ag engine used in tractors and skidders and other various heavy equipment. Obviously those applications abuse the powertrains much worse than any OTR application. It wasn't a matter of getting the bugs worked out at all, in fact it was nearly perfect when it debuted in Case equipment. The only real problem was a crappy oil filter system that would have been fine on OTR applications, but couldn't keep up with the dirty conditions off-road.

If the 5.9L motor was a great powerplant, how can the 6.7L not be? Its practically the same motor with a slightly larger bore, and a DPF and EGR system. And I don't know how you can even compare the 6BT to a 6.2L Detroit motor that was a joke then, and makes GM guys puke a little when you bring it up now.

The 7.3 was always a reliable motor, but it was never a powerhouse until 97 when it was turbo'd, intercooled, and direct injected.

The Dodge is a great truck, it has been since the First Gen. I'll openly admit that until 04 the Dodge Auto's were basically junk if they weren't properly built. But unlike the General, and Ford, Dodge offered, and still does offer, a MANUAL transmission, which is what every diesel should be equipped with for hauling anything. The other big advantage that Dodge, and even Ford have over GM is a real truck front end. IFS is a joke, and I'm clearly not the only one who thinks so.

I'll say this, and I've said it before. Ford has hands down the best chassis. From a super strong frame, to a radius arm front solid axle, to proven reliable Dana axles. I personally don't like the exterior styling, but it works for some people.

Dodge has the best engine, no question... Its why Ford and GM guys pull their original diesel engine to swap it for a Cummins. The Aisin automatic (which FYI is available only on C+C models) is also the best built trans out there, its a medium duty unit, unlike the light duty Allison, 68RFE, or Torqshift, and it weighs a ton. The 68RFE has also shown to be an incredibly reliable transmission so far, even with aftermarket upgrades. I personally like the Dodge styling and new 2010 interior the most as well, although the Ford interior is very impressive. The AAM axles are excellent, but I worked for Dana for years, so I've seen the limits of both (I was a test technician first at the TRP plant in Ottawa Lake, MI, then the ASG plant in Maumee, OH).

The Chevy has a nice motor, and an excellent transmission. I'd take the Allison over anything but the Aisin, and if I was gonna really hot-rod one of these trucks, the Allison would be my choice because of its aftermarket support (although at the extremes the clutch-clutch shifting of the Allison is a huge problem, and most guys swap to the 47RH of the 12V Cummins trucks, even the Aisin can't handle it). The rest of the Chevy doesn't impress me... The frame hangs low, the front end isn't suitable for hard work (like logging, farming, or hard off-road use), the interior looks like it was pulled out of an Impala, and the body is way too big for those tiny wheels and tires.

Most of this is my opinion, and you aren't going to change that. However my opinion is based on what I know, and how I use trucks. Each of these trucks have strong suits, and shine in their own application. Then again, the Ford shine's on the outside, but the motor is one of those things where I'll say to the end, you can polish a turd all you want... Its still a turd.

the 5.9 and 6.7 are only related, bore and stroke, turbos, and over half the motor parts are redesigned. the new cummins has had sufficient enough problems with emissions that soot filled egr and burnt turbos has prompted dodge to buy back a large number of trucks. gm has implemented the emissions regulations with the fewest problem of the 3 manufacturers, not withstanding the emisions stuff is crap anyway.

i made a mistake about the 6.2l, it was at the end of its life cycle when the 5.9l was introduced. the 6.5l when turbo charged was a better comparison to the 5.9l, still not as good though.

if the aisin is only available on cab-chassis trucks, maybe we should compare it to the allison 2000/3000/4000 trannys? your right in that the allison is a light duty unit, it isnt meant for use in more than a 1 ton truck...

you other opinions are just that , i have mine also. ive had ford, dodges and chevy over the years and to me the best overall package was the chevy. i dont really find the ifs to be a limitation , but do think that these trucks should have the option of either ifs or solid axle. the lack of the stick is potentially a problem, but then do i really want a stick and solid axle in my $65k luxury truck when i have the allison and a ifs that is very capable for 90% of my uses?

 

[046]

had a very nice 97 cummins 12v 4x4 with 120k miles when I sold it.... reason it had an auto and I wanted a stick.... yanked 30k+ lbs with that rig....

took me almost 2 years of searching, but I finally found it. it's my current ride: 96 cummins 12v 5sp 4x4 with 67k miles. best in town mileage is 22.5, but usually average 20 mpg...

for me having a stick in town means control of what rpm your engine operates at. instead of dealing with auto tranny slip. added 4-5 mpg over my auto cummins for in town driving.

naturally yanking heavy loads is always easier with a stick. still don't understand why dodge for 2nd gen 12v, put auto transmissions in almost all the 3/4 ton cummins trucks.

the lack of the stick is potentially a problem, but then do i really want a stick and solid axle in my $65k luxury truck when i have the allison and a ifs that is very capable for 90% of my uses?

 

[motoroilmccall]

the 5.9 and 6.7 are only related, bore and stroke, turbos, and over half the motor parts are redesigned. the new cummins has had sufficient enough problems with emissions that soot filled egr and burnt turbos has prompted dodge to buy back a large number of trucks. gm has implemented the emissions regulations with the fewest problem of the 3 manufacturers, not withstanding the emisions stuff is crap anyway.

i made a mistake about the 6.2l, it was at the end of its life cycle when the 5.9l was introduced. the 6.5l when turbo charged was a better comparison to the 5.9l, still not as good though.

if the aisin is only available on cab-chassis trucks, maybe we should compare it to the allison 2000/3000/4000 trannys? your right in that the allison is a light duty unit, it isnt meant for use in more than a 1 ton truck...

you other opinions are just that , i have mine also. ive had ford, dodges and chevy over the years and to me the best overall package was the chevy. i dont really find the ifs to be a limitation , but do think that these trucks should have the option of either ifs or solid axle. the lack of the stick is potentially a problem, but then do i really want a stick and solid axle in my $65k luxury truck when i have the allison and a ifs that is very capable for 90% of my uses?

Compare the Aisin to the bigger Allison transmissions. The Aisin is used all the way to class 7 trucks, and it holds its own quite well.

The 6.5L wasn't much better than the 6.2L, I owned one... For a month (that's all I could stand of the thing).

As far as a $65 luxury truck goes... Why don't you just buy a Cadillac? I love laughing at guys who have trucks like yours. Its not a work truck, its a toy. Yeah, it probably pulls a toy hauler, or camper around, but that is NOT a work truck. If all you do is haul the highway with a camper or toy hauler, then you really aren't testing the truck like I am. I've used Ford's and Chevy's too. A 2000 F-250 that was a great truck as long as I ever used it, and a 02 Chevy 3500 that was always a headache. It would drag frame left and right, and bust tie rods and CV shafts like it was a K-Nex toy... But it sure did ride nice that whole time .

 

[ropensaddle]

Compare the Aisin to the bigger Allison transmissions. The Aisin is used all the way to class 7 trucks, and it holds its own quite well.

The 6.5L wasn't much better than the 6.2L, I owned one... For a month (that's all I could stand of the thing).

As far as a $65 luxury truck goes... Why don't you just buy a Cadillac? I love laughing at guys who have trucks like yours. Its not a work truck, its a toy. Yeah, it probably pulls a toy hauler, or camper around, but that is NOT a work truck. If all you do is haul the highway with a camper or toy hauler, then you really aren't testing the truck like I am. I've used Ford's and Chevy's too. A 2000 F-250 that was a great truck as long as I ever used it, and a 02 Chevy 3500 that was always a headache. It would drag frame left and right, and bust tie rods and CV shafts like it was a K-Nex toy... But it sure did ride nice that whole time .

My ram has that assassin tranny so good to know it feels shifty but never had a problem with it yet.

 

[djmercer1]

Compare the Aisin to the bigger Allison transmissions. The Aisin is used all the way to class 7 trucks, and it holds its own quite well.

The 6.5L wasn't much better than the 6.2L, I owned one... For a month (that's all I could stand of the thing).

As far as a $65 luxury truck goes... Why don't you just buy a Cadillac? I love laughing at guys who have trucks like yours. Its not a work truck, its a toy. Yeah, it probably pulls a toy hauler, or camper around, but that is NOT a work truck. If all you do is haul the highway with a camper or toy hauler, then you really aren't testing the truck like I am. I've used Ford's and Chevy's too. A 2000 F-250 that was a great truck as long as I ever used it, and a 02 Chevy 3500 that was always a headache. It would drag frame left and right, and bust tie rods and CV shafts like it was a K-Nex toy... But it sure did ride nice that whole time .

but the aisin from what ive read isnt available in the 'regular' 3/4 and 1 ton trucks we are talking about. the 68rfe is a revised 48fre that was ok, but not great, the 68rfe is still new and the jury wont be back for a couple of years. no doubt the reputation of the aisin is good, comparabe to the allison, another husky-stihl debate infact. if we want to talk about the stirling/4500/5500 we should then compare to the kodiak, not the silverado, and the ally 3000/dmax combo...

the reason gm doesnt offer a stick, is why dodge put auto in almost all the finished trucks---theres no market for the stick. while i prefer a stick, in most situations the new intelligent autos are making that option extinct....

unfortunately(or fortunately) there is no option for towing 15klbs other than a diesel truck.... but my truck does infact work by hauling work gear(excavators and construction supplies), and visiting remote construction sites, but at the end of the day it is still civilized enough to take the wife and kids for a drive in.....