I replace my AT fluid about every 40,000 miles. Its a pain in the a s s to replace it hence replacing it 40,000 miles. My oil change is every 3,000 miles. But thats a heck of allot easier to replace. Heck I even replace power steering fluid sometimes. The one thing I hardly ever replace would be brake fluid. Out of all the years I have own cars and their life span. I have never once had problems with the brake fluid aspect being a problem other then general wear and tear of pads etc. The last time i did bleed them it was pretty clear so it was bordering pointless to me. What amazes me is how many people don't do radiator flushes.

I used to N coast my AT, with engine on, for every glide and hill and stop light I found. But I've been coasting in N a lot less lately for two reasons: 1) AT started shifting funny at stop lights. 2) at low speeds, when the TC is not locked, there is only a miniscule improvement in FE. Certainly not enough to warrant No. 1, or worse . :-)

But I'm still slipping it into N for glides over 1/4 mile. I've not had any trouble with the D-N or N-D shifts at highway speeds. On N-D shifts, I 'blip' the throttle first, to get the engine rpm's closer to where they'll be in D.

And that's my two cent's...

P&G combined with EOC is one of only two FE mods I use, the other is the HF transmission. With these two I have obliterated my EPA rating.

EOC Coast
 

I've been Engine-off coasting in Neutral for over a year and probably 20K miles on a Honda I-4 tranny with 130K miles on it. No ill effects so far -- it whines in neutral, but as I recall, it always did. The fluid needs changed -- going synthetic (when I can get an hour or 2 in the garage) :rolleyes:

This singular method produces a significant boost in FE -- so the plan is to continue...

-RH77

I've started changing out tranny fluid, one tranny drain pan at each oil change. On my car the tranny pan holds 2.5 qt. so that's what I drain and replace. Do it every 4K miles or so and it works out to be nearly a perfect match with the 20K change cycle the owners manual recommends.

OK, I did some serious calcs in Excel to work out how much old + new fluid are left in tranny after x number of change cycles as above. For your car, it's up to you but I'm comfortable with it for my car. My motivation - I'm changing to synthetic ATF at about $6/qt and I can't afford the whole thing at one shot. So I'll change 2.5 qt every month or so, pretty soon it will all be synthetic, in practical terms.

Rick,

The manual states no faster than 35mph and for no longer than 50 miles.

From my experience in road cycling, accelerating to a high speed and coasting back to a low speed and repeating is the best way to have a horrible average speed and waste TONS of energy. I can't see how it would improve fuel economy in any way. BUT, I've never tried it, so maybe you guys are right.

When you change velocity, that requires additional power. I would think it's far better to maintain steady speed/power levels.

And how practical is it anyway? Are you going to yo-yo down the road in traffic? Dip to 45mph on the interstate and get run over? lol

Keep an open mind Velo. It is a proven technique. Don't laugh at people who are willing to do something to conserve energy.

Yeah, it's a little different. It really works. There are threads where people have explained why it works, if you want to look around for those.

veloman -

I don't think you can compare road cycling to P&G. For MPG competition, P&G is a proven technique. There is no debate on the subject.

I think that steady state mostly holds true for speeds at or below 35 MPH, where the car doesn't have to fight aerodynamic friction.

What are the racing techniques in those super-aero enclosed recumbent bikes?

CarloSW2