Would you get a diesel if making a new car purchase?

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wahoowad

Minister of Fire
Dec 19, 2005
1,669
Virginia
We are contemplating a new car purchase and the wife is interested in a Volkswagen diesel. I've never owned a diesel and don't have any friends who have had one either. Do they require more frequent maintenance? Is the improved MPG worth the added cost of buying higher priced diesel fuel?

Thanks for any input.
 
I've not owned a diesel car but most diesels use more oil, or that is, more oil per change. I also do not like the smell and of the couple that I know they do not get that good of gas mileage.

On gas mileage, we have been considering a new car but hate to give up the gas mileage we are getting now. Since the car was new (we keep track of every tank) we have averaged over 36 mpg and very few can match or beat it unless going hybrid. One of my problems too is getting in and out of a car. Most are just too low and the doors are built so that you have to lean back while getting in. My body is not made for that, or at least it is not good since some injuries. Therefore I am a bit limited on types of cars.
 
I've got a diesel truck. Some things you would want to consider.

Weather: Used to be a big deal but I don't even plug mine in during the hardest of Winters and I've never, ever had a problem with it starting as long as I let the glow plugs cycle. You need to let them warm up, especially if you've got a turbo.
Oil: My truck takes about 12 qts to change the oil. If I went to a quickie-lube place it would cost me about 75-100 bucks for an oil change.
Fuel: You will need to change your fuel filter every 20-40k and if you don't do it yourself it will cost you anywhere between 100-200 bucks. Also, diesel isn't cheap anymore. If you're commuting, its a wash and will cost you about the same as gas when you factor cost vs mileage. If you're towing then diesel is much cheaper.

I like the diesel engine but in all honesty its not worth the extra money when you figure I'm driving <10k miles / year. Sure you can get a million miles from the engine but the rest of the vehicle will rot away around it by the time you get back the additional expense. I was attracted to the idea of using WVO but could not find a dependable source. Low-end torque is great for fun. I like it, but wouldn't lay down the 8k for the package if I wan't towing massive weight. My truck was a salvage/flood. Only way it made sense for me.
 
I had my 2000 VW Beetle TDI for about 225,000 miles. Not even sure why I sold it. A guy in New Mexico paid top dollar for it and had it shipped to him. I got 964 miles on a tank of fuel once (PS: It took a while to reprime the pump after stalling out at that intersection :) ). You can do the math yourself as far as $/gal. I got 52 mpg MINIMUM with that car. Of course, diesel isn't cheap here like it is in Europe (hello, why not?). My car had a single injection distributor pump. I think the new ones are common rail, with electrically controlled injectors. Not sure of the pollution control technology (NOX) on the Passat. Last I heard it was self regenerating on the Jetta/Golf, but the Passat might need a change of urea cartridge like the Merc - totally not sure, but look into it. I loved the way it drove - much torque. Go to http://www.tdiclub.com . Great group. I miss them. Nothing similar for MINI Cooper, which I've had now for 67 k miles with no problem except a water pump (knock on wood). MINI only gets 42 mpg.
 
I would personally go gas, especially in a passenger car. The upfront cost and maintenance for diesel is higher, and the fuel savings isn't what it once was. Nothing against diesel, just not as cost effective as it used to be. All the clean diesel stuff they have to put on them has really hit their efficiency and reliability compared to some older ones.
 
velvetfoot said:
But the torque is awesome! :)

Yes it is.

Do those have much turbo-lag or do they spool pretty quick at the low end? Torque = good. Torque + boost = hang on.
 
GO DIESEL!! I love them, I have had 3. Dont listen to some of the comments, they arent true with modern diesels. The up front cost is higher. Maintenance is pretty mch the same. Oil changes are 10k miles, it is diesel oil, so its a little more expensive, not much, none of the 3 jetta tdi's i had have burnt any oil. get the timing belt changed per the manual, thats super important!

My jetta has 160,000 miles on it. Its wonderful. I think I would opt for a golf next, just a little smaller.

please feel free to contact me with any specific questions (PM). I have had a 86 TDI jetta (134k miles), 1998 TDI (about 114k miles, then hit a deer and totaled it), currently driving a 1999.5 jetta TDI with 160k miles.

They have never done me wrong, all worked great. Cold starts are no problems. I still get 50mpg. it is hardly noticable the difference from gas to diesel. at speed it is actually quieter than a gas engine (as it has to rev lower).

I drive about 10-15k miles a year. If I drove a gas vehicle, it would cost me $1000/year extra. Thats a lot of extra expense. and who knows what fuel prices will do. it is also great getting about 600-650 miles to a tank, pretty nice not having to go to the gas station so much.

great cars, VW makes a wonderful machine!
 
The only diesel engine I own is in a tractor so no owner experience. I can tell you an associate drives a new VW diesel and its very hard to tell based on noise, smell, performance, that its not a gas powered car.

I like that biodiesel is good option too if you care about energy security, sustainability and all that.
 
"Diesel" oil is not that special. I buy it from walmart for 10$ per gallon for delo400 15w-40. Perhaps VW has chosen to specify something very specific? My big honkin 2 quart oil filter is 10$ from walmart as well, motorcraft brand. Oil changes are actually pretty cheap.

Look at used car prices, the premium you pay up front for the diesel is recovered later on when you sell. Compare a 2000 gas golf with a 2000 diesel golf for example.

I daily drive a 2000 model 7500lb diesel truck with a 7.3 liter, huge, diesel engine. I only go 8 miles each way to work. 15 mpg commute and 20 mpg highway. I get 12 mpg towing heavy which I do regularly and which is the reason for the truck. It is cheaper to daily drive the truck than to buy a second MPG vehicle. An older, manual, VW TDI would be my commuter of choice.

Brand new VW diesel eh? You'll need to consider the technology on these newest engines. Due to our lame emissions laws you are seeing technology on these engines that could make them a totally different vehicle than the TDI diesels that VW was famous for 10 years ago. It could be that the newest diesel is the best ever or it could be only slightly better than gas. Test drive it! a gas engine getting 40 mpg will be much slower to drive than the diesel or be in a smaller vehicle.
 
I used Delvac 1 at the prescribed 10,000 mile oil interval.
It was interesting how soon the oil got black, compared to a gasser.
Diesel cars are so prevalent in Europe, you know it's gotta drive well.
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http://autospeed.com/cms/A_112231/article.html
 
The oil is cheap if you do it yourself, but if you don't its however much over 4 quarts + filter (so $6/quart x 8 plus the regular change....). I don't know if there's really extra maintainence, but it can get expensive quick if something goes wrong.

If you're not going to tow something and just looking for passenger travel then gas is better. Save the cash for when you buy the all-electric commuter car.
 
btuser said:
The oil is cheap if you do it yourself, but if you don't its however much over 4 quarts + filter (so $6/quart x 8 plus the regular change....). I don't know if there's really extra maintainence, but it can get expensive quick if something goes wrong.

10$ per gallon for diesel oil is 2.50$ per quart. The TDI takes less than 5 quarts so 12.50$ for oil. Plus price of oil filter. You can cheaply change the oil, pretty much the same as a gas engine for this car. Or pay to have the dealer do it. In any case, this is a very small cost of ownership and not an increase in cost for diesel vs. gas.

If something in the engine breaks, it can be much more expensive to repair than a gas engine. This is the single fear I have about diesel engines in general. Everything else is peachy.
 
velvetfoot said:
The potential for damage to expensive parts is why I wouldn't use biodiesel, esp. in the US.

I think it was an issue before all engines switched to bio-diesel-friendly gaskets+o-rings. Now the major danger is scrubbing the gunk off the inside of your tank and fouling a couple fuel filters because bio-diesel is almost a detergent. It is actually a very good additive in regards to lubricity for ULS diesel.
 
I read somewhere a few years ago that the bio-d can wash down the cylinder walls past the rings. There might also be quality issues in the US.
 
I don't know about "pump-diesel", but at work, we are mandated to use D-20 - 20% bio.

It seem to hold more water, and clog more pre-filters, than regular Diesel. Granted, it's in an automobile, and get used 5+ days a week. Some of our equipment sits for months (3+) at a time; unfortunately 1/2 tank, or less, of fuel [been hitting my head against a brick wall with this!] You can actually see a rust line inside of the tanks; metal or plastic; when they try to run it. I've started, a couple of months ago, to use StarTron in the seldom used tank. I'll see, hopefully better, results in the fall.
 
For me heating oil (diesel) tank I have treated it with both a biocide and power service clear diesel ( http://www.powerservice.com/cd/ ). I butn about 30 gal / year and have about 4 or 5 years of fuel left.... so I dont want it to go bad on me. Those seemed to be the right things to toss in the tank.... might help your condition.

For what its worth, the tank is about 60 years old, when I removed the float there was nasty black ooze on it, but that seemed to be old and non active as the fuel was still pink/clear, as it should be, and this fuel has been sitting for about 4 years now). So I am not too concerned about the need for biocide, but the clear diesel should help with moisture and stability..... i hope...

Never worries about any of this for my diesel car though.
 
That reminds me. One thing that hasn't been mentioned for the o.p., if you get a cold snap early in the year, and it hasn't been cut with enough kerosene yet, the diesel could gel and you could be at the side of the road. Happened to me once.
 
That price is like the sale price of cheap dino oil man! I haven't seen $10/gal 15w40 in years to be honest.
The TDIs all need synthetic oil. Oil change (oil and filter) will run $35-40 depending on the oil and filter that is bought.

I use same oil in everything I own that takes oil though, so doesn't matter on cost to me really. Case (6 gals) of synthetic is about $140 from the Shaeffer dealer.


Highbeam said:
btuser said:
The oil is cheap if you do it yourself, but if you don't its however much over 4 quarts + filter (so $6/quart x 8 plus the regular change....). I don't know if there's really extra maintainence, but it can get expensive quick if something goes wrong.

10$ per gallon for diesel oil is 2.50$ per quart. The TDI takes less than 5 quarts so 12.50$ for oil. Plus price of oil filter. You can cheaply change the oil, pretty much the same as a gas engine for this car. Or pay to have the dealer do it. In any case, this is a very small cost of ownership and not an increase in cost for diesel vs. gas.

If something in the engine breaks, it can be much more expensive to repair than a gas engine. This is the single fear I have about diesel engines in general. Everything else is peachy.
 
I think the request for synthetic arises from the possibility of cooking the oil in the turbo. If you get off the highway the exhaust is really hot and the turbo will build up a layer of coke in it if you're not careful. I added a remote starter to my truck that has a turbo-timer which allows me to exit the truck with my keys while the truck does a "cool down" for 3-5 minutes. I've checked the exhaust temp with a heat gun and there's a couple hundred degrees difference just after 2 minutes at the tail pipe, but who knows what's happening under the hood.

I also added a secondary oil filter (oilguard I think) that filters down to 1 micron and allows me to extend oil changes out to 25-30k (or so they say). My thought was to use synthetic and get my money's worth, but I drive a whopping 5k a year now so I'm dumping it regardless.
 
wahoowad said:
We are contemplating a new car purchase and the wife is interested in a Volkswagen diesel. I've never owned a diesel and don't have any friends who have had one either. Do they require more frequent maintenance? Is the improved MPG worth the added cost of buying higher priced diesel fuel?

Lots of other factors to consider-how long is her commute? If she does 50 miles each way five days a week I'd say yes-if she has a commute like my wife (3 miles a day each way), I'd say no. Maintenance costs will net you some savings as maintenance generally means changing the oil-no spark plugs, wires, or distributors (do gas cars even have distributors anymore?) to worry about. There's also longevity of course. A well cared for diesel will simply last a lot longer, but again, that's another factor-if she's going to want a new car in 10 years its a moot point. If not, keeping the car 20 years would likely be no sweat. I would actually try to ask around a little more because as you can see, most diesel owners here have trucks (myself included), which is really an apples to oranges comparison. No one buys a diesel truck because of the good fuel mileage ;) There are VW forums out there but the names escape me. Personally I chose a diesel because of the ability to burn vegetable oil. I've been doing so for nearly 3 years and 100K miles-its not for everyone though.
 
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