Volkwagon Diesel (TDI)

[mbcijim]

So I bought my first new car a few weeks ago. It is a Volkswagon Jetta TDI model, which means it's diesel. I put 1,200 miles on it so far. My average MPG is 43.8. I wanted a stick but the dealer swore that they don't get better mileage anymore, that technology has changed and they are roughly equal in MPG.

My first reaction to the high MPG is 1) I am never, ever going back even with $2.00/gallon gas, 2) We are all talking about hybrid, electric, when the volkswagon diesel is a very good solution right here right now that works.

Some other things that surprised me was no emissions testing is necessary (at least in Pennsylvania where I live) and that oil changes are every year or 10,000 miles, whichever comes first. Both are nice selling points although very minor in the scope of things.

 

[webbie]

That may be my next car after I wear out my Passat. I only get 31-32 on the highway....but I understand how the decent mileage is addicting. We hardly ever take the Subaru (25mpg) on long trips since that would be a waste of money and gas.

I don't see gas going down to $2.......even as a fluke. Maybe $3.

 

[Jack Straw]

I always wondered what the cost difference would be.
I ran these numbers with local area prices
43.8 MPG
400 miles driven
9.13 gals used
9.13 gals x $4.25 per gal= $38.81


Typical gas equivalent
35 mpg
400 miles
11.43 gal used
11.43 x $ 3.87 per gal=$44.23

Does the diesel option cost more than the gas equivalent?

 

[webbie]

I think it depends on many factors.

Jim mentioned a combined MPG of 43+
I don't think many gas cars can attain that.

Also, people are driven by much more than the exact price - I'm 100% certain Jim could afford to drive a 25MPG car, but maybe he has a thing for efficiency? Lots of buyers do.

There are other factors also. Some diesels have better towing specs......

I happen to like the ride of VW.....it has that german feel in the suspension and steering.

So there are lots of factors involved. I looked at the Jetta before I bought my Passat, but it was an older model then and not quite as refined. But the newer Jetta is almost as big as the Passat.

 

[begreen]

Yep, the new Jetta TDI is nice. I was looking at their wagon when I picked up the camper. Almost hitched it behind to take home. A friend has the older Jetta TDI which averages 55mpg and loves it. Still, locally diesel costs as much or more than premium gas, so I am happy with the Prius getting the same mileage on regular.

 

[DexterDay]

Yep, the new Jetta TDI is nice. I was looking at their wagon when I picked up the camper. Almost hitched it behind to take home. A friend has the older Jetta TDI which averages 55mpg and loves it. Still, locally diesel costs as much or more than premium gas, so I am happy with the Prius getting the same mileage on regular.

Yep... My buddy at work has a 6 yr Old TDI (manual) Jetta that gets 53 MPG. They advertise less than what they do actually get.....

He lives about 45 miles from work (highway) and I live almost 60 miles away (highway also). My 2011 Focus only gets about 34.5. I looked at the Jettas. But as much as I drive, its hard to justify the extra $$$$$. Driving about 40,000 miles a yr os hard on any vehicle/wallet. But I live next to Amish. So I must drive to where the work is...

My next truck will be a diesel. The 03 F-150 SuperCrew FX4 has some miles on her now. Time for a new one. A 1 ton SuperCrew w/ Diesel. Dollar for Dollar the HP and Torque is unmatched.

 

[MasterMech]

So I bought my first new car a few weeks ago. It is a Volkswagon Jetta TDI model, which means it's diesel. I put 1,200 miles on it so far. My average MPG is 43.8. I wanted a stick but the dealer swore that they don't get better mileage anymore, that technology has changed and they are roughly equal in MPG.

My first reaction to the high MPG is 1) I am never, ever going back even with $2.00/gallon gas, 2) We are all talking about hybrid, electric, when the volkswagon diesel is a very good solution right here right now that works.

Some other things that surprised me was no emissions testing is necessary (at least in Pennsylvania where I live) and that oil changes are every year or 10,000 miles, whichever comes first. Both are nice selling points although very minor in the scope of things.

Sounds like the dealer has an auto in stock and really didn't want to order you a manual. I love stick shift small cars. I've found that many auto's have STUPID programming that try's to keep them in the highest gear possible for best MPG's regardless of throttle position. My Canyon will attempt to shift like it has a V8 under the hood (and the associated stump pulling low-RPM torque) instead of the 3.5L 5 cyl it has. I can "manually" shift/drive it to a combined MPG of aprox. 20 MPG whereas if I let the vehicle shift as programmed it will drop to 16-17 MPG or worse. Just taking it out of overdrive for hilly, winding roads and hill climbs on the highways makes a big difference.

Those long oil changes are common now, even with a gas motor. Factory interval on both my truck (2005) and my wifes car (2011) is 10,000+ miles. Almost every mfg is over 7500 mile intervals now. Diesel combustion byproducts are less harmful to the oil than gasoline combustion byproducts. Semi-trucks go for amazingly long distances in-between changes. 3mo/3000 miles is a dead horse. If you do your own oil changes, do yourself a favor and buy the highest quality synthetic oil you can find in your area to make that motor go forever.

There is still some stiff resistance to diesels in the US because of:

1) The bad taste left in our mouths from Detroit's late 70's/early 80's offerings. The result of American mfg policy at the time. Cheaper is better right?

2) The assumption that the small diesels used by the Europeans in their cars are the same as the workhorses under the hoods of semi's, pickups, and off-road equipment.

3) The higher price of diesel at the pump. Here, currently it's $.50 a gallon difference. That makes no sense to me.

We have a family friend with the Jetta TDI wagon and he does occasionally tow a small pontoon boat with it. Try that with your Prius.

 

[coaly]

The reason many automatics get better mileage then the older ones is due to torque converter locks. There is always fluid slippage inside a torque converter like a fan on the engine pushing the fluid against a driven fan connected to the wheels. Once up to speed, this slippage is minimal, but can still build up heat, and cause wasted motor RPM's. Newer autos are using a electromagnet that locks the engine and wheels together to avoid all slippage when possible. Sometimes when this locks, it will feel like another gear, or overdrive. That's how much slippage there was with older automatics on the highway. Vehicles with the lock and a 4 speed auto will find if you shift down to 3 on a hill and back off, you can get the converter to lock in 3 rd and run a lower RPM than letting it slip all the way up the hill in 4th.

Keeping injectors clean to get a good spray pattern is essential for the best mileage. I was a tech for VW-Audi back when the diesels came out. Using Power Service fuel conditioner helps, (and is required to add lubricity to the diesel of today) and when changing the fuel filter, pour it in the filter straight to run it on the cleaner / lubricant. This cleans the injector tips of any carbon to get the very fine atomized mist required.

Europeans will also run about 1000 RPM higher in lower gears then in the US. They will always run 3 rd on all back roads and only "D" to let it go into high on the highway. Owners manuals actually call for this, but American drivers tend to use "D" for everything and lug our engines more. This prevents converter lockup to engage as well.

 

[lukem]

My BIL has a '03 with a manual and gets 48 in mixed driving.

It boggles my mind why there isn't a half ton diesel pickup available in the US. I would be all over one. Something with about 150 - 200 HP and 300 - 400 lb ft and gets mid to upper 20's mpg would be awesome.

 

[Seasoned Oak]

My BIL has a '03 with a manual and gets 48 in mixed driving.

It boggles my mind why there isn't a half ton diesel pickup available in the US. I would be all over one. Something with about 150 - 200 HP and 300 - 400 lb ft and gets mid to upper 20's mpg would be awesome.

GM has a 4.5L diesel they already developed and tested just in time to get mothballed when the big depression hit a few years ago and PU sales went through the floor. It is 300HP and only the size of a 350 gasser so it fits in everything. Word is that it can do 30MPG in a full size PU. Hope they change their mind and bring it back. My sons 6.6L GM duramax PU does over 20MPG Hwy on a regular basis. Not bad for a 6000 LB truck.

 

[nate379]

It's Volkswagen, no such thing as "Volkswagon"

I get 43-45mpg in mine, an 05 Jetta. Been meaning to put a different 5th gear ratio in, but haven't had the time.

I pay about the same for diesel as pump gas costs. I have a bulk tank at my house that holds 300 gallons. I run through about a tank a week in the Jetta (550-600 miles)

 

[nate379]

I think your talking about a torque convertor clutch? It's just a large friction disc(s) similar to the ones used in the transmission. Been in just about all car/truck auto trans made in the last 20 years.

The reason many automatics get better mileage then the older ones is due to torque converter locks. There is always fluid slippage inside a torque converter like a fan on the engine pushing the fluid against a driven fan connected to the wheels. Once up to speed, this slippage is minimal, but can still build up heat, and cause wasted motor RPM's. Newer autos are using a electromagnet that locks the engine and wheels together to avoid all slippage when possible. Sometimes when this locks, it will feel like another gear, or overdrive. That's how much slippage there was with older automatics on the highway. Vehicles with the lock and a 4 speed auto will find if you shift down to 3 on a hill and back off, you can get the converter to lock in 3 rd and run a lower RPM than letting it slip all the way up the hill in 4th.

 

[MasterMech]

The reason many automatics get better mileage then the older ones is due to torque converter locks. There is always fluid slippage inside a torque converter like a fan on the engine pushing the fluid against a driven fan connected to the wheels. Once up to speed, this slippage is minimal, but can still build up heat, and cause wasted motor RPM's. Newer autos are using a electromagnet that locks the engine and wheels together to avoid all slippage when possible. Sometimes when this locks, it will feel like another gear, or overdrive. That's how much slippage there was with older automatics on the highway. Vehicles with the lock and a 4 speed auto will find if you shift down to 3 on a hill and back off, you can get the converter to lock in 3 rd and run a lower RPM than letting it slip all the way up the hill in 4th.

Keeping injectors clean to get a good spray pattern is essential for the best mileage. I was a tech for VW-Audi back when the diesels came out. Using Power Service fuel conditioner helps, (and is required to add lubricity to the diesel of today) and when changing the fuel filter, pour it in the filter straight to run it on the cleaner / lubricant. This cleans the injector tips of any carbon to get the very fine atomized mist required.

Europeans will also run about 1000 RPM higher in lower gears then in the US. They will always run 3 rd on all back roads and only "D" to let it go into high on the highway. Owners manuals actually call for this, but American drivers tend to use "D" for everything and lug our engines more. This prevents converter lockup to engage as well.

This post is just freakin' excellent.

Manipulating the TC Clutch is exactly what I'm doing on my little truck to get the better mileage. Problem is, with the little 3.5L it likes to run at 1800 RPM with the throttle wide open, 4th gear TCC locked. It will then downshift straight to 2nd , and rev to 5000+ to regain speed before shifting back into 4th. The cruise programming just likes to pretend that 3rd gear doesn't exist and I find that very annoying considering all the on-board computing power available on todays vehicles. If it's not in cruise, it's better, but it still prefers to unlock the converter rather than downshift. At anything over 30 MPH that just doesn't make sense from a fuel economy standpoint and really even the driveability suffers. This truck would be stellar with a modern 5/6 speed transmission in it and if GM fired their driveability programmer. FWIW this isn't the only GM vehicle (or any mfg'r for that matter) that I've driven that acts like this.

 

[coaly]

No, Nate; I'm referring to a electric winding that becomes a magnet called a torque converter lock controlled by the computer. It's an electromagnet that makes a solid connection between engine and transmission. My Land Rover has a switch next to the shifter for "Manual Mode" that will not shift and run locked. (When in Low Range) Just like a standard transmission. Shifting into 1,2,3 or 4 puts it directly in that gear. When in low range, you can select the gear you want and hit a second button "Hill Descent Control". This runs the ABS pump and applies brakes to keep it from going faster than when the button was pushed. A slow speed cruise control if you will. This is for extremely steep declines that maintains each wheel rotating the same speed. Or steering on the side of a cliff if you don't want to be in the vehicle in case it goes over at walking speed.
The Rover also has a second valve body that changes the shift points to a "Sport" position when the button next to the shifter is pushed in high range. It only locks you in the manual mode in low range. The ZF automatic is one of the best automatics made with imperceptable shifting. You see the tach drop and know it shifted, you can't feel it. BMW uses the ZF and I believe most vehicles today are using electric solenoid operated locks. They are available as an add on as well.
They started in '96. (broken link removed to http://www.patentstorm.us/patents/5505284/claims.html)

Maybe you're referring to the same thing, but I think your're referring to a mechanical clutch. I was a VW mechanic before we were called "Techs". Beetle, Type I, Type II and Bus. They were all air flow control injected before there was any injected vehicle in the US. Then they started water cooled engines, then later added the diesel in the 80's. Same cast engine block and bottom end, that shows how heavy duty the VW water cooled engine was. We couldn't keep the head gasket from leaking on the diesels. It would either leak into the coolant tank blowing it up like a ballon or leak down the front of the block. Valve clearance between piston and valve was controlled by head gasket thickness. They had notches on a tab outside the gasket so you knew what thickness gasket to use. So using a thicker gasket or sealer decreased compression. A thinner gasket allowed valves to contact the carbon on top of the piston. I took many apart that had valve imprints in the carbon ! Wasn't much we could do with head gaskets back then. That WAS over 20 years ago, thanks for the reminder !!

Another story was the very first truck race at Pocono Raceway close to our dealership. We were supplying the pace truck, a VW pick-up for the race, and the night before, a little clip snapped inside the transmission. It was a brand new vehicle - the next model year coming up - with no parts available in the states yet. VW had to fly another new 5 speed transmission to the track overnight for the race next day. That race was in the 80's. Not the Nascar truck races of today. It was heavy trucks. A field of Bob Tails behind that pace truck ! It was easy to shift a little too hard pulling out in front of the leader doing only 40 to 60 mph in a 4 cylinder diesel.

 

[Seasoned Oak]

It's Volkswagen, no such thing as "Volkswagon"

I get 43-45mpg in mine, an 05 Jetta. Been meaning to put a different 5th gear ratio in, but haven't had the time.

I pay about the same for diesel as pump gas costs. I have a bulk tank at my house that holds 300 gallons. I run through about a tank a week in the Jetta (550-600 miles)

More MPG are possible Also pretty impressive is the 64.6 MPG from a non hybrid ,non diesel Chevy cruze.(mentioned at end of story)
http://wot.motortrend.com/couple-se...ord-in-2012-volkswagen-passat-tdi-202867.html

 

[nate379]

I'm sure I could get 60mpg if I really wanted to but I have no desire to drive like an 80yr old women and I doubt anyone else behind me does either!

 

[ihookem]

I always wanted a VW deisel. My won't even get in one though. I have an 05 GMC deisel PU. It gets 20 @ 2,000 rpm's. I cam e across a 91 Saturn, 5 peed stick. I avr 40 mpg. My worst is 37.5, my best is 42.47. I run this car when I don't need to run my truck. I'm going synthetic oil, better tires and non ethanol gas. to see if I can get 46??? Who knows. I wish we would be more concerned about fuel milage.

 

[Seasoned Oak]

Looking for a car my daughter can use, the Cruze ECO for $149 lease getting 42 MPG looks pretty good. NO doubt there will be something better in 3 years so no sense buying it and taking a shellacking on the trade in.

 

[Corey]

I always wondered what the cost difference would be.
I ran these numbers with local area prices
43.8 MPG
400 miles driven
9.13 gals used
9.13 gals x $4.25 per gal= $38.81


Typical gas equivalent
35 mpg
400 miles
11.43 gal used
11.43 x $ 3.87 per gal=$44.23

Does the diesel option cost more than the gas equivalent?

Interesting numbers. If I drive my car sensibly, it will get 31mpg on E85....

31 mpg
400 miles driven
12.90 gallons used
12.90 gallons x $2.99 per gal=$38.58 ...essentially comparable to diesel, while either leave gasoline in the dust.

The flip side is, putting the accelerator to the floor and letting the turbo work it's magic, it would most assuredly pass a TDI like the diesel wasn't even in gear. So the option exists to get even more mpg by trading some top end HP. I'm actually hoping to do in the coming years, as I noted a guy recently dynoed 514 hp with a 3mm smaller turbo than I have.

I wish we would be more concerned about fuel milage.

I wish we would be more concerned about where our fuel comes from and the actual cost per mile of driving.

 

[nate379]

My fuel comes out of the ground about 700 miles north of here.

 

[TMonter]

Don't forget to factor in the price of the car and maintenance. When maintenance comes due on a diesel you pay a premium compared to a gas motor.

 

[TMonter]

There is still some stiff resistance to diesels in the US because of:

1) The bad taste left in our mouths from Detroit's late 70's/early 80's offerings. The result of American mfg policy at the time. Cheaper is better right?

2) The assumption that the small diesels used by the Europeans in their cars are the same as the workhorses under the hoods of semi's, pickups, and off-road equipment.

3) The higher price of diesel at the pump. Here, currently it's $.50 a gallon difference. That makes no sense to me.

We have a family friend with the Jetta TDI wagon and he does occasionally tow a small pontoon boat with it. Try that with your Prius.

Don't forget EPA regulations as well. Most euro diesels will not meet the current US EPA regulations even though their emissions per miles driven is lower.

 

[Jags]

Don't forget EPA regulations as well. Most euro diesels will not meet the current US EPA regulations even though their emissions per miles driven is lower.

Yeah, because of the stupid way that we rate emissions output. Per mile makes a helluvalot more sense than per gallon (like we do it)

 

[nate379]

Not really, normal maintenance items costs about the same.

Don't forget to factor in the price of the car and maintenance. When maintenance comes due on a diesel you pay a premium compared to a gas motor.

 

[velvetfoot]

We just this hour came back from a week in Ireland. Nearly every vehicle there, far as I can tell, is diesel. Our rental was a diesel Focus five speed that drove great. There are a lot of small diesel cars there that I wish we had available here. I had a TDI Beetle for 225,000 miles, and I really loved that car. I'm no petroleum industry expert, so I can't understand why diesel (and heating fuel) is so expensive compared with gasoline.