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Remember that Sammy Hagar song? Well, I just got back from a trip to the U.P. (Michigan). Before I left, I decided I would see what kind of mileage I could coax out of my wife's 04 VW Jetta TDI with manual tranny.

Before I left, I added nitrogen :) to my tires to bring them up to 48 psi (3 psi below the sidewall, but wayyyyy above VW's recommended 28 psi).

I used airconditioning approx. 60% of the trip. total miles per GPS were 621.8 miles round trip at an average speed over the whole trip per GPS of 53.6mph.

I'm kind of blown away, and I'm disappointed I won't be able to give you the mpg, as I'm showing just under 1/2 a tank!!!! I've got 643 miles on this tank and still showing just under 1/2 a tank!!! Unbelievable. I NEVER thought our car could do that.

The REAL point of my post and the reason for the title of this post (it's in jest), is my experience driving at 55mph.

Some thoughts:

Semi-truck drivers don't like it (almost everyone comes barreling at you and one sped around me and literally cut me off with half his trailer still left to pass me.)

MANY SUV's passed me-more than any other type of vehicle.

On two lane roads, if you're doing 55mph, everyone is doing 55 mph behind you. You're FORCING THEM TO GET BETTER GAS MILEAGE!! :Banane07:


I NEVER had to tap my brakes or turn cruise off because someone was in my way. It was kind of nice just to cruise, although you REALLY have to turn your attention to the rear view mirror. Intially it was quite un-nerving.

While I was cruising at 55, I couldn't help but think about the waste of fuel every time some big SUV came flying by, many times pulling big trailers loaded with big, gas consuming toys.

The truth is I CAN drive 55, and I foresee the U.S. going back to the national 55 mph limit.

The fastest I have ever made the trip is 4:45, going an insane 80mph almost the whole trip-aggressive driving to say the least. This trip, each way took exactly 5:45-a one hour difference, but the trip was a lot less stressful even accounting for the bogies on my 6.

Now everyone sing with me..."I CAN drive...55!!!!" :bananajump:


Ciao,

Andy

Guess what?

If one of those big rigs are not speeding too much, you get an incredible draft!

I got nearly 75mpg at 70mph when I'd normally get 60mph - a lot of people don't recommend it, but those are my results.

I will also run parallel on access road when I can avoid traffic lights so I meet less agressive drivers and go 55mph.

You only get the draft when they are in front of you, right?

No.
You can get a draft if they are at an angle from you as well as when they are passing you.

Here is an excerpt from this thread:

http://www.cleanmpg.com/forums/showthread.php?t=1510

Drafting:

* Close-in: Close-in: Pulling into < 1.0 seconds directly behind a semi-tractor trailer rig at speed. Results can be astounding but with severe consequences as the probability of an accident increases at a higher rate then does your FE ! Doubling the EPA or a short time period is doable under the right circumstances.

* Distant: Pulling into > 1.0 seconds directly behind a semi-tractor trailer rig at speed. Results are OK as there is slightly less wind drag to break as well as being much safer.

* Surf: Pulling in just behind and along side of semi-tractor trailer rig at speed attempting to reduce your own aerodynamic drag by riding in the broader wake the rig ahead and to the side of you has created. Results are minimal but better then driving naked into the wind.

* Traffic Side: Traveling at a slower speed in the far right lane while traffic passing creates a bow wake effect across the entire highway/road in which you are traveling. Results are excellent the heavier the congestion is as long as there is some speed difference between you in the far right lanes and the traffic in the left lane(s) as you are receiving both the high FE from the slower speeds as seen in the steady state speed tests above as well as receiving a lowered aerodynamic drag because of the wake helping to push you along.

Hi Andy:

___Driving 50 -55 mph on 55 mph limited roadways is hard. Driving the same on 65 mph limited one’s takes more then skill, it takes … You know what I mean ;)

___What I highly recommend is that you begin to RR as it is the safest way to travel unimpeded for both you as well as traffic behind. Trust me as I have told a thousands others. Just do it, hold it, and watch your rear view. You will notice those tractor trailer rigs moving out ½ mile back vs. 2 truck lengths back. Not RR is doing a disservice to my own personal goal of using less fuel but doing the same for those behind that are tapping brakes and doing the wiggle dance as they come in way to hot. You do not have a flashing sign on your truck saying “Caution - I am going 55 mph - Please Be careful” so RR and do all of us a favor.

PS: I cannot wait to hear how that tank ends up as it could be the start of a whole slew of TDI drivers finally taking their vehicles to the FE they so much deserve. Keep us posted, OK!

___Good Luck

___Wayne

"Bogies on my 6", I love that phrase. Gotta remember that one.
.
_H*

Ehh, driving ~60mph on a highway posted at 65mph isn't that bad. Generally speaking, traffic flows around me just fine as long as I'm on the 60mph side of things. Sometimes people even follow willingly! Slow moving trucks ahead are a gift that makes life even easier. RR works, and I also make use of climbing/slow vehicle lanes whenever they are available. (Some people get annoyed that I "block it" so they can't use it as right-side passing lane...their problem, not mine.)

I'm sure it's a bit riskier to drive below the limit rather than above it, but I can't really say that I've had any close calls with being rear-ended in the last 5 months. It's major fluctuations in speed (DWL) that cause problems more than anything else, so I don't do that when there are people on my tail. (Side note: That actually makes DWB in heavy traffic easier since the people behind me perceive continuous motion while the other lanes are standing still, and tend to be more relaxed/less likely to start an incident.)

I realize this is a whole other debate, but I haven't decided if I buy into the argument that driving below the speed of traffic wastes more fuel collectively. On the one hand I understand the logic, which is that me driving slower causes someone behind me to brake (waste) and then accelerate (waste again.) At the same time, how does that compare to if that driver just kept on going at the original speed of ~70mph rather than my 58-60mph? What if the driver had the wherewithall to pay attention and coast down or change lanes rather than braking? Not saying the effect isn't there, just that it seems a bit more complicated than slow driving = causing waste.

I was out last night doing some hold-the-iFCD tests on I-95, where
in the later evening traffic was fairly light and I could let my
speed drift down under 50 at times. Every so often I'd see a
"bogey on my six" [i love that] and a couple of quick flicks on
the hazards got their attention early enough that they were able
to a> wake up, and tell the person on the other end of the phone
"hold on a sec", b> take note of my slower speed, and c> change
lanes well back of me to go around without having to change speed.
By being a little proactive, I was probably lessening their
potential MPG hit when they didn't have to tap the brakes or
turn off CC or whatever. [Helps that there are *four* lanes]
.
I know that several folks have had their differences about delta
speeds and the "lower MPG" of everyone else having to cram up
behind the slow hypermiler and then pass, but that's really a
non-problem if people are PAYING ATTENTION and just flow smoothly
around a slower vehicle. If they're keeping proper following
distance, there's even plenty of room to do it in heavier traffic.
But unfortunately we all know the grim reality of *that*...
.
_H*

I filled the tank yesterday, because I had to give the car back to my wife...


Miles travelled was 681.57. Verified by GPS and highway mile marker correction.

Refill was 12.157 USG of #2 diesel.

Mileage for this trip was 56.064 mpg. Not bad for not trying too hard. Cruise control 95% of the trip at exactly 55. GPS said 53.2 mph avg over the entire trip.

Now here's a funny story. A guy at work just traded his Ford Taurus in for a Nissan Pathfinder, and he asked me how much longer it took to get up to my destination. I told him 1 hour more exactly from my best time doing 80 mph. So going both ways that's an additional 2 hours. So then he had me calculate how much $$$ I saved, and my usage came to 4.1 gallons at $12.73 for the entire 681 mile trip. That brakes down to $6.37/hr. Then he asked me what my time was worth...doh.

But it is MY time, and just because I'm not saving a hypothetical dollar figure of what I THINK my time is worth, doesn't mean that is the only savings. That was 4 gallons that I left in the system for my little part of conservation. If I change my driving habits over an entire year, the savings will be in the hundreds of $$$. Not a bad bonus. (tax free even :) )

Tell him who was going to reimburse you the $6.37/hr? Because at 80mph your time was worth $0.00. A persons time isn't worth anything if they aren't getting paid for it. Ask him how much he got paid to make the same trip in shorter time.

I'll fudge - speed by drafting a big rig. :D

Tell him who was going to reimburse you the $6.37/hr? Because at 80mph your time was worth $0.00. A persons time isn't worth anything if they aren't getting paid for it. Ask him how much he got paid to make the same trip in shorter time.

We need a beer smilie for this comment. Spot on!
:beer:

Where I live it's even worse. The speed limit is 65mph. This week I was driving 65mph and this guy in his dodge pick up was riding my bumper and flashing me the entire time. On the left of me there was a car but it was like one car length ahead of me. The dodge switched to the left lane and tried to pass and cut me off there was no way he was going to squzze between me and that car. I'm already experienced in this area. I lost one of my cars to this kind of a situation where a guy cut me off, totalled my car and ran.

So I downshifted to 4th and floored it and he was still gaining on me. I downshifted again, this time to 3rd and put a couple of cars on him. Nobody is cutting me off. I'd rather waste a little more gas than have my car screwed up.


Next thing happened today.
I was driving 60mph in the far right lane and I look in my rear view mirrow and a truck is right on my bumper. He was so close that I couldn't even see his grill on the side mirrows, only his headlights. And he would continue to get closer, I thought he was going to ram me. So I down shift to 4th and floor it. I put some distance on him and continue driving 75mph. Then I see a huge figure closing on me like a freight train. He was hauling ass. I was going 75, he must of been going at least 85-90mph. It was that same truck. He wasn't slowing down, I thought my car is going to be his new hood ornament.

Me and my cousin got really scared, so I put some huge distance between that truck and me. Talk about a psycho driver. I hate Cali.