Hey GOLF 2.5ers, Gas Prices Eatin at Ya!

[MLue1]

Wid Gas prices getting more expensive saving $ becomes more important. After owing the Golf 2.5 for several years now from Stock, to IE Stage1 Tune, to IE Stage2 Tune I can offer what my Son and I have found in terms of Gas Milage.

The Golf 2.5 is NOT good on gas in City stop and go driving and will never be, the milage will suck with 5 cylinders burning gas every revolution instead of 4 cylinders in other cars. Combined city/highway driving the Golf 2.5 milage is pretty good tho.

The two biggest things that we found that save fuel was using Castrol 5W30 motor oil and the IE Stage1 Tune. I personally don't try to save on gas I like the engine to respond quicker, SURPRISE SURPRISE using lighter weight 5W30 allows the engine to respond quicker by reducing reciprocating drag by being a lighter weight oil compared to 5W40, it does help saving gas by 1 mile per gallon. Using a lighter weight oil does not wear your engine faster, we have over 300K on our 2.5 engine and my Son revs it to 7000 rpm all the time with IE Stage2 and the engine doen't burn any more than 500ml (1/2 quart) between oil changes and compression is still very good. The VW Stock Tune sucks for gas milage, upgrading to IE Stage1 will give you better gas milage as the Tune optimises the fuel trim which improves performance and drivability, as well it gives surprising better gas milage, if you drive the car in the same manner. The bad part is IE Stage1 recommend that you use a higher octane gas (91). Recently my friends in BC where gas is now hitting $2/litre, have been using 89 octane with IE Stage1 and report the milage is still better than with the Stock Tune.

Feel free to posts your findings and opinions below.

 

[Wascally Wabbit1]

Yeah, we're at $6.39 a gallon for 91 octane here in Southern California. I also get better mileage with IE Stage 1. The transmission tune will eat up gas in sport mode as it bumps the rpms up quite a bit, but it makes for a fun drive. I average about 30 mpg. I think the 2.5L is a pretty good compromise between fun to drive and fuel economy.

 

[SliMbo2.5]

Not sure what I was getting prior to my UM stg 1 since I got it shortly after getting the car to get rid of that stupid rev hang(manual trans). I have not messed with oil weight and have been averaging 28-30 mpg during the summer and 27-28 mpg during the winter(winter drop to be expected) with mild romping here and there. These have been with mostly city driving but with a recent move I am now taking the freeway in the morning, so we'll see where the mpg goes. Although I am averaging 75mph on that morning trip into work with this 5 speed.

 

[Maxey]

I'm still on the stock tune, but looking to get the IE Stage 1 soon. I've been commuting 50 miles round trip lately, most of it on a 65mph, dual lane highway (I drive around 70mph). It's always windy as hell where I live, so I typically get around 24 or 25 mpg on the way to work (into the wind) and around 29 or 30 on the way home. 2010 Golf 2.5 with 140k miles. Now that's it's finally warming up the mileage will get a little better. My other car, a 2018 Alltrack, gets about 3 to 4 mpg more in the same circumstances, so I consider the 2.5's consumption to be pretty reasonable. The 2.5 uses only negligible amounts oil between changes in case you're interested.

 

[MLue1]

I'm still on the stock tune, but looking to get the IE Stage 1 soon. I've been commuting 50 miles round trip lately, most of it on a 65mph, dual lane highway (I drive around 70mph). It's always windy as hell where I live, so I typically get around 24 or 25 mpg on the way to work (into the wind) and around 29 or 30 on the way home. 2010 Golf 2.5 with 140k miles. Now that's it's finally warming up the mileage will get a little better. My other car, a 2018 Alltrack, gets about 3 to 4 mpg more in the same circumstances, so I consider the 2.5's consumption to be pretty reasonable. The 2.5 uses only negligible amounts oil between changes in case you're interested.

If your 2010 Golf 2.5 is a 5 Speed manual you will have the lower sport gearing, the engine will be reving alot higher at highway speeds. The gas savings will eventually pay for the Tune

Good engines burn only a small amount of oil....

 

[Maxey]

If your 2010 Golf 2.5 is a 5 Speed manual you will have the lower sport gearing, the engine will be reving alot higher at highway speeds. The gas savings will eventually pay for the Tune

Good engines burn only a small amount of oil....

Yes, I should've mentioned mine is the manual. Pretty good gearing around town, lately I've been putting in 4th gear at 30mph, and 5th at 40mph, unless on inclines or need quick acceleration. In 5th at 40mph it's turning right around 1600rpm, isn't anywhere near to lugging at that speed, actually pulls nicely if needed. But I do wish the highway rpms were a little lower, turns just shy of 3400 @ 80 mph. So if the gas savings will pay for the tune, you just gave me all the justification I need.

 

[MLue1]

Yes, I should've mentioned mine is the manual. Pretty good gearing around town, lately I've been putting in 4th gear at 30mph, and 5th at 40mph, unless on inclines or need quick acceleration. In 5th at 40mph it's turning right around 1600rpm, isn't anywhere near to lugging at that speed, actually pulls nicely if needed. But I do wish the highway rpms were a little lower, turns just shy of 3400 @ 80 mph. So if the gas savings will pay for the tune, you just gave me all the justification I need.

My buddy used to be a VW Apprentice, spent he spent a lot of time rebuilding transmissions. Its being a long time and I have never done this mod but i believe the transmission is the same as the MK5 rabbit or Diesel, you can actually change the 5th gear out to a higher overdrive ratio without removing or cracking open the transmission. The end of the transmission comes off exposing the 5th gear which can be replaced with a higher ratio gear. The mod can be done in like an hour, if you have all the parts, it would be a good project to look into, have at it.

Cheers

EDIT: I found a Youtube Video HERE that shows you how to do the 5th Gear Overdrive Mod, save $ on gas

 

[SliMbo2.5]

My buddy used to be a VW Apprentice, spent he spent a lot of time rebuilding transmissions. Its being a long time and I have never done this mod but i believe the transmission is the same as the MK5 rabbit or Diesel, you can actually change the 5th gear out to a higher overdrive ratio without removing or cracking open the transmission. The end of the transmission comes off exposing the 5th gear which can be replaced with a higher ratio gear. The mod can be done in like an hour, if you have all the parts, it would be a good project to look into, have at it.

Cheers

If I did more freeway driving I would definitely consider doing it. Especially around here where the speed limit going north is 75, which means everyone is doing at least 80.

Like @Maxey said, when I'm around town I mostly stay in 4th unless I have a stretch of road with no lights and can just cruise.

 

[Maxey]

My buddy used to be a VW Apprentice, spent he spent a lot of time rebuilding transmissions. Its being a long time and I have never done this mod but i believe the transmission is the same as the MK5 rabbit or Diesel, you can actually change the 5th gear out to a higher overdrive ratio without removing or cracking open the transmission. The end of the transmission comes off exposing the 5th gear which can be replaced with a higher ratio gear. The mod can be done in like an hour, if you have all the parts, it would be a good project to look into, have at it.

Cheers

EDIT: I found a Youtube Video HERE that shows you how to do the 5th Gear Overdrive Mod, save $ on gas

MLue, wow, if true that's pretty incredible. Maybe sometime down the road, as I need new front struts and also would like to get the IE tune so have some other expenses to take care of for now. I don't mind the high rpm on the interstate from the aspect of comfort as the 2.5 is such a smooth motor, but I know it's just a waste of fuel sitting at 3400 rpm.