diesel engine/future

[mutcth]

Originally Posted by SteveH

This stuipid thing gets WORSE fuel mileage than my 1/2 ton gas truck did.

I'm not sure its apples to oranges though - there are more variables than the diesel engine.

Comparing four-wheel-drive crew cabs, the 3/4-ton GM diesel weighs 1500 lbs more than the 1/2-ton gasser.

Supposedly GM is freeing up some of the government money it just got to push through some backlogged product development projects. I'd be surprised if their light-truck diesel (which is almost done) wouldn't be on that list.

Got to say, I welcome the new technologies in diesels. They're cleaner, quieter, and smoother. The difference in driving a late-90s Cummins-equipped Dodge and a 2007 (I've spent a good amount of time in both) is night and day.

Tom

[CanoeStream]

Originally Posted by TomR

I do believe that the new and "newer...2010" pollution rules have greatly diminished the benfits of a diesel pick up...other than strong torque...which if you pull on the very heavy side may still lead you to a diesel.

Tom, there is nearly nothing new about 2010 requirements as pertains to the current status of diesel trucks. Or 2009. Or 2008. This is seat of the pants and I may be off in some moderate ways. You can really get into it if you delve into dieselstop.com (Ford) or dieselplace.com (GM). Other background at Ultra-low sulfur diesel - Wikipedia, the free encyclopedia

But a general timeline is that the govt decided in 2002 to move to lower sulfur diesels. There were particulate goals set in there somewhere too. Pickup trucks at the time had diesel engines in the 225-275 HP range. Truck manufacturers started making changes based on the govt timeline & goals. I know that my 2006 had a 3rd generation engine based on phasing in of emission requirements -- and my 2006 was built for 200ppm or less sulfur (so-called LSD).

The govt required that all diesel-selling stations transition to having ULSD available starting Autumn 2006 but I believe the drop-dead date was about Feb-Mar 2007. That transition was accompanied by the 2007 model year 4th gen engines that could burn nothing but ULSD ... or risk more frequent, costly repairs.

Where did the mileage go? There probably was extra hardware put on the engines to comply with emissions requirements; that would subtract some power to operate. But I'm going to point instead at a fictitional Jesse Ventura character battling Predator in a careening, hopped up Hummer. Remember the mess the auto companies got themselves into by judging "what the buying public wants?" We were supposed to want suburban assault vehicles that could compete with our SO's Lexus SUV. It prolly wasn't necessary but they upped many engines in Gen 3 to 300HP. Gen 4? They added a second stage to turbos and upped HP significantly again! You can currently get your GM Duramax with 365 freakin' HP. Wish I was a teenager all over again... The unnecessary increase in HP is where the mileage went -- you'll about never need 365 HP in 99.9% of towing situations. Is that more than a lot of OTR trucks? And thus a HD 1/2-ton chassis with a midsized diesel would really appeal to me towing a 25' Safari. C'mon Detroit! Or Alabama... Or Mississippi... wherever automotive headquarters will be in 5 years.

So yes, I don't get anywhere near the old-time mentioned 20 mpg while towing. The very best towing mileage I've gotten under very rigorous control was 16.5 mpg (55mph, no acceleration to keep speed on hills between here and Duluth. I'd never have the patience to keep that up on a long drive). My usual towing mileage in a mix of driving at 65mph is around 14.7 mpg. Cruise control will kill another 1-2 mpg depending on how hilly it is (never use it except on flat). My old Nissan Titan would rarely get 11 mpg towing and would drop below 10 mpg if I wasn't careful. But my Duramax did get 19.5mpg average not towing on a recent 2600 mile trip with average highway speed probably just under 75mph. I'm a happy camper.

The amazing companion to my Duramax is the smartest transmission in the world - the Allison. We did a trip to Glacier & Waterton Lakes in Canada this fall. On any descent I could set my speed in Tow-Haul mode and it just wouldn't speed up. Try that in a gasoline powered truck.

All that being said.. I challenge any gasser TV in the middle lane to keep up with me as I come down the entrance ramp on a freeway. In the sweetspot of 3000 rpm or so I can out-accelerate most every tow combination on the road. Now... just why would I need an extra 65 HP? Why do I need 300 HP? Mileage goes out the tailpipe -- always has, always will.

[Road Ruler]

Originally Posted by CanoeStream

All that being said.. I challenge any gasser TV in the middle lane to keep up with me as I come down the entrance ramp on a freeway. In the sweetspot of 3000 rpm or so I can out-accelerate most every tow combination on the road.

Well I don't know about going down hill but going up hill we travel in the center lane and have passed a number of slower moving vehicles. Note powered by a 6/gasser.

[TomR]

Originally Posted by CanoeStream

Tom, there is nearly nothing new about 2010 requirements as pertains to the current status of diesel trucks. Or 2009. Or 2008. This is seat of the pants and I may be off in some moderate ways. You can really get into it if you delve into dieselstop.com (Ford) or dieselplace.com (GM). Other background at Ultra-low sulfur diesel - Wikipedia, the free encyclopedia

I thought there was a new particulate? requirement coming in 2010 and that we are getting new diesel engines from Ford and GM to meet the new rules...with UREA "filters" (Chrysler aleady meets the new (2010) requirements?). Perhaps I am off base?

I do participate on the two diesel site you reference...just not too often.

My point was not that a diesel did not have more power and may be more fun to tow with...or race up the center lane ...just that the diesel advantage has diminished greatly...particularly the MPG advantage. Also, many do not look forward to the UREA issue...along with the current "re-gen" requirement. And then there is the initial cost factor which has gotten pretty dear.

Still...sure would like to have one...tempted to reach back to a used GM LBZ 2007 1/2 Classic...which preceded the ULSD engine...most problems were worked out of that version of the Duramax pre-ULSD. Tom

[Mike Leary]

If I had to re-power my Isuzu/GMC Turbo 470 transmission, I'd do the Duramax combo.

[RedSHED]

Originally Posted by mutcth

...
Supposedly GM is freeing up some of the government money it just got to push through some backlogged product development projects. I'd be surprised if their light-truck diesel (which is almost done) wouldn't be on that list.
...

Read in the SAE rag today that GM has axed the small D-Max, apparently for good. Their concern appeared to be around the cost of certification vs the size of the market.
Same journal had an article on Ford's continuing development of the 6.7L Nav replacement, but nothing on the Dodge diesel.

[Rebee]

Back to comparing oranges and oranges. Some things to remember when comparing fuel economey in different vehicles is rear end ratios and tires.

I ordered my truck so I could get the smaller gears (3.73). Everything I saw on the dealer lots had the 4.11 gear sets. The taller gears will keep the engine on the top of the power curve but will also burn a lot more fuel. The 4.11 rear is good for jack rabitt starts and towing very heavy equipment. It was not needed to pull my A/S.

My tires are street all weather tires. The tread pattern is not what I would call aggressive. I have used them to move my trailer in muddy conditions but only in low 4wd and very slowly. I do not consider them good for a lot of "off road" events. The more agressive the tire tread the more fuel it takes to roll them on the road.

[mutcth]

Originally Posted by RedSHED

Read in the SAE rag today that GM has axed the small D-Max, apparently for good. Their concern appeared to be around the cost of certification vs the size of the market.

Good grief. They couldn't have figured that out before spending millions in development costs? To be fair, the big drop in the pickup market probably shifted expectations a lot.

I guess I'll shelve my diesel Avalanche dreams for good...

Tom

[SteveH]

Originally Posted by mutcth

I guess I'll shelve my diesel Avalanche dreams for good...

Tom

Tom,

In my opinion after now owning and driving a rather new Diesel, you've not lost anything. The newer ones with the DPF (Diesel Particulate Filter) in the exhaust system, and the needed regeneration cycle it mandates, removes all of any fuel mileage advantage the Diesels ever had. But, at least the fuel is still higher priced.

Just like our government...mandate higher fuel efficencies one one hand, and then mandate ULSF (Ultra Low Sulfur Fuel) on the other causing prices to go up, and then to top it off, mandate the DPF system causing mileage to go down. What a bunch of morons.

What? Me bitter????

[bimpy]

I'm going to change the subject slightly here to "diesel past". A recent "barn find" has turned up an 82 Chevy with 6.2 and 97000 miles. Truck seems to be in excellent shape,starts runs and sounds good. Can anyone give advice about the 6.2? This is a little before my time and there seems to be quite a bit of anamosity toward older diesels esp. GM. Thanks, Vince

[Smartstream]

I just read an article about the "Green Car Journal" awarding it's "2010 Green Car of The Year Award" to the Audi A3 TDI Diesel. Of five finalists three were hybrids, Honda, Toyota, and Mercury and two diesels, VW Golf TDI and the Audi.

One of the Audi big wigs apparently have been very vocal about the U.S. Govt. pushing manufacturers to the hybrid. He says they should set the target MPG and let the manufacturers find the best way to get there.

I personally feel that our Govt. follows the lobbyists and money rather than the science. I have read that 80% of the luxury cars sold in Europe are diesel. The Jaguar XJ6 sedan has a diesel option the does 0 to 60 in 8.3 seconds, has a top speed over 140 mph and gets 37 mpg. My '72 XJ6 does 0 to 60 in 8.5 seconds, has a top speed of 126 mph and gets a whopping 16 mpg. If I could figure a way to import a new Jag I would be a very happy camper.

I have driven diesels as my primary vehicle since 1982. My first was a '79 Peugeot. I have also had Ford, Chev, and currently a Dodge diesel pick-up. I have four collector vehicles that are diesel as well as a tractor and a boat. Of coarse the Airstream is diesel.

Long Live the Diesel.

[Smartstream]

Originally Posted by bimpy

I'm going to change the subject slightly here to "diesel past". A recent "barn find" has turned up an 82 Chevy with 6.2 and 97000 miles. Truck seems to be in excellent shape,starts runs and sounds good. Can anyone give advice about the 6.2? This is a little before my time and there seems to be quite a bit of anamosity toward older diesels esp. GM. Thanks, Vince

I drove a 82 6.2 for several years. It's a capable engine if you don't run it too hard. Running loaded at full throttle up the hills will insure an early death. Back off the throttle, drop a gear and stay to the right and it will live longer. The engine also has weak head bolts. They are not reusable, pull the head and buy a new set of head bolts. You will learn when you blow the first head gasket. At 97.000 it has already blown a head gasket or it will very soon. The starter was also a weak spot. I bought a NAPA with a lifetime warranty and replaced it several times. The manual said not to pre-fill the fuel filters when you change them. You are supposed to install the filters dry and crank the engine with the starter until it starts. You get to buy a new starter with each filter change.

[Beginner]

The main reason the Government is backing the Hybrid and the Hydrogen fuel cell to power cars and trucks is because the public will still be tied to a vendor for fuel, and an easy way to collect road taxes. Bush's buddies big oil (Shell Oil for instance who talked about placing hydrogen filling stations) will still be guaranteed income. Efficient batteries would be developed if half the money being dumped into fuel cell research were diverted to battery development. But no, the Govt still must have their easy way to collect road taxes (tax on each gallon of Hydrogen or gas) and pay off their buddies, big oil. The battery car would plug in the wall and the actual cost of charging up the vehicle would expend one tenth the energy it takes to generate the liquid hydrogen.

Beginner

[FreeWilly]

I am a big fan of the diesel engine, although were they are headed I may change my opinion. This new Ford diesel is a good prospect, since it was in part designed with the help of the Europeons. They have been useing diesels for many years. Cummins is a great engine, I am not a big fan of the truck, after ownig a few in my fleet. The Ford chassis are much better, but the Engine, (6.4) was a let down. I wish they would offer the 7.3 in the future again

[SteveH]

Originally Posted by FreeWilly

The Ford chassis are much better, but the Engine, (6.4) was a let down. I wish they would offer the 7.3 in the future again

Because of the emissions laws in this country now, I don't believe you will ever see that engine again, or even one simular to it for that matter.

Additionally, if the manufacturers can't figure out how to get the fuel mileage back up on the new Diesels, I predict that Dielsels in non-commercial use will soon be a thing of the past in this country.

[FreeWilly]

SteveH that will be sad

[SteveH]

After totally servicing this new(er) 2008 GMC 3/4 ton Duramax Diesel truck that I traded for (and I do mean totally...changed engine oil and filter, transmission oil and filter, lubricated the front suspension, changed the air filter, the fuel filter, the transfer case oil, and the differential grease, and adding a fuel additive) we took a trip to visit inlaws last week, and driving 65-70 without the airconditioner, and in mostly cruise control, the fuel mileage is now at 18.7 mpg on the highway. I still have not had the oportunity to tow the Airstream with the truck.

This is now up to the fuel mileage that my '07 1/2 ton gas truck got under the same driving conditions. I suspect the main "problem" was the air filter. Sorry to say, the fact that this air filter was in the condition it was in, illustrates to me the service history this vehicle has "endured".

From the looks of the oil that drained out of the engine, and the particulate matter that was left in the drain pan, I am going on a regiment of short mileage oil changes for a while in an effort to clean the inside of the engine. I suspect because of the fact this truck is 1.5 years old, was for sale on a used vehicle lot, and had 53,000 miles on the clock, that it was a lease vehicle and had less than adequate service attention in it's life. At this point, I can only hope no serious damage was done to the drive train as a result.

When you buy used, it's like a crap shoot, and you just take your chances.

[dene57k]

Anyone have experience with the 5.9 cummins. I am looking at a 36ft Air Stream with 48 K miles. I am wondering about the weight ratio of this unit, and where to find weight info on this unit. I am a bit out of my element in this arena, and don't want to make a mistake at this stage of life. I have had a 7.3 Naturally aspirated Navistar in a 29 Ft Ford. Great engine...not great power..but great mileage at 15 mpg.
any insight appreciated on the AS with 5.9 cummins...and weight issues..

[handn]

Gas cars ran badly for almost ten years starting in the early 70's. Finally technology caught up with the emission mandates.
I am babying my 2000 7.3 Power Stroke and will not buy a new light truck diesel until the new ones perform equally well.
If the Power Stroke dies (not too likely), I will go to a gasser.

[Finch]

im just glad i have a 04 cummings, great milage and no DPF. the 5.9 will pull your house AND you nieghbors with no problems (pulled 18k up the 8 in san diego at 60mph, no issues)