So I recently changed my oil and transmission fluid on the TL. I expected to get better gas mileage, but I'm shocked! I gave her, her first oil change with Mobile1 synthetic oil (likely from non-synthetic oil). The next day I flushed the transmission as well. Now, I normally get 330ish on a tank; the first tank after, I got 350. I filled up today and got just over 370! Wow! I wont argue I guess!

 

Wow that's pretty nice, I have to change my tranny fluid, I have never doen it since I've had the car...... maybe it's time.

 

I just did mine at about 53k. I don't think it's ever been done. It's pretty easy and not too expensive. I'll probably do it every 15 - 20 thousand miles...

 

wow...i have 120k and never had it done...does it make that much of a diff? hwy driving I assume? there's a DIY also, right?

 

Yeah if there is a DIY that would be great. I probably kow how to do it, but I just want to make sure I don't miss anything.

 

I got a new tranny about a year and half ago. Should i do it too? Ever since i put I/H/E on my car i now get from 200-250 on a tank Well i do have 93K miles , I will be doing Seafoam soon along with new spark plugs. Hopefully it helps.

 

yea, my car gets HORRIBLE mileage. I am going to seafoam and get new spark plugs as well. let us know how it works out for you.

 

I get anywhere from 200-250 average 230 on a tank? 300 sounds ridiculous...that'd be amazing if I could get that kinda work I have 80K ish on my TL-S is this like horrible or around average?

 

For what trans fluid? Yea there are a ton of them. Search. there are great DIY's

 

These "miles per tank reports" can be wildly erratic.

It's better to report miles per gallon. And, even then, MPG values can vary significantly for a number of reasons.

Certainly how the car is driven along with the mix of city and highway driving can have a huge impact. You'll see much worse mileage if you stomp on the gas in stop and go traffic than if you cruise at highway speeds.

And there are many other items than can come into play.

Here are a few off the top of my head:

- Tire Pressure
- Spack plug condition
- Air Conditioning use
- Excessive in place engine idling

And the list goes on...

So you have to be careful when measuring fuel economy and when you attribute changes to any particular change that you've made.

My general impression is that you won't see much in the way of fuel economy changes from engine oil and transmission fluid changes. (Unless you've had some sort of serious oil or fluid breakdown.)

Bob

 

Ok, well I get 200-250 miles in a tank in city driving, almost never use A/C, tire preassure is fine, I drive like a grandma all the time, I need new spark plugs and i think thats about it. Either way, i always get an average of 200-250 miles a tank, no matter how differently i drive or how much i use the A/C. Its always in those numbers.

 

Whats a "spack plug" ?

 

Those "per tank" don't surprise me since these are fairly heavy V6 powered cars. They will just not do well in city driving with a lot of starts and stops.

I typically get 25 to 26 MPG in my 1999 TL but that's probably 80% highway driving. (An example fill-up would be 340 miles traveled on 13.2 gallons.)

I've very happy with that mileage given the size and performance of the car.

But I'd expect much worse mileage in mostly city driving.

Still it wouldn't hurt to check your plugs out.

Bob

 

LOL!

I don't know but I should probably replace them with "spark plugs" ;-)

That's what I get for buying aftermarket parts off of eBay.

Bob

 

Hahaha.... that's funny. I was kiddin bout the spack plugs thing. Just givin you shit.

 

Whats fine tire pressure? (just wondering) cause every one runs something different. I run 38-42 (depending on where im going)
your mileage is about the norm for cit driving only. Not much to improve there.

 

Yeah i'm getting like 18-19 mpg in my 02 TL-S....all city driving, I don't think the spark plugs have been replaced, but the car was my parents before so they could have had it done. My tires are at like 32ish more like 34 or 36 but thats what the thing on the tires say...

My year TL is supposd to get 19 so i don't feel like i'm losing out on mpg...it just hurts doing 40 dollars every week-10 days as a high school student...but you gotta pay to have a great car like this...

 

I believe with the EPA revisions we are rated at 17MPG which is what everyone seems to get all city driving.

I know it hurts right in Cali where premium is almost $3.40 a gallon! Last fill up for me was $50 bucks! That sucks some serious ass right there.

 

35-40 on my 225/40 tires.

 

Tires say maximum, not what you should run. Recommended is printed in your door. A good rule of thumb is 80% of maximum, then adjust to your own liking.

Try filling up if not EVERY day or just about every day (and when the TL is down fill up a Expedition the same way)

Just checking

 

I used to get 420+ a tank before seafoaming and new spark plugs... I almost hit 500... ALMOST... and then my tranny died.

 

Good example of a decent shape car for the gas mileage.

 

These cars get great highway mileage. With 3 people on board & luggage, I managed 31.2 MPG last week, averaging around 70-75 MPH. I haven't check the around town figure, but 18-20 MPG sounds about right.

I keep 35 PSI in the tires.

 

To those who have never done a tranny flush and have high miles-dont do it. I work at a dealership and I was going to do one on my last car, which had about 150k. It had never been done, and every mechanic told me not to do it. With higher miles and a tranny flush, it will sometimes break things loose. Sometimes its better to leave undone, it kind of acts like an equilibrium. Just thought I would save a few trannies.

 

Thats one of the reasons acura doesn't want flushes done period on their cars. Thats also why the recommend just a simple 1 drain and fill. It doesn't completely add all new detergents into the trans. It mixes with old.

 

I drive 50:50 city:highway and get around 24 mpg on mid-grade. On my drive to work on surface streets, I'm usually sitting in bumper-to-bumper traffic. On my drive home, I hit the highway and usually after a mile or so of b-b traffic, I'm running 85+ mph, if traffic permits.

Thing is, I don't accelerate hard (I'm one of the slowest off the line), I anticipate braking and don't tailgate so I hardly ever have to slam on my brakes but I'll drive as fast as traffic will allow (and I know there are no cops around).

Sure I'd like to get better mileage but I'm happy with what I get, taking into account what kind of car the TL is.

 

I used to get at least 360 per tank, but after I replaced the OEM Michelin tires with Yoko Avid V4S's, I am lucky if I get 300 before the gas light comes on. I seemed to have lost at least 3 mpg. Maybe it is a winter gas blend, but it was winter before I got my tires changed (and cold as sh*t here in VA ... at least for a VA winter).

Not sure what is up with it. Tires are set to 33/34 PSI. I am not very happy with the tires at all, but that is a different thread that I may start after taking back to the tire installer for a 3rd time on Saturday.