Maintance on 2006 subaru

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Feb 25, 2009
I need some info on a 2006 Subaru Lagacy 2.5L 4 cyl Turbo 70,000 miles. Bought from Carmax and previous owner had service records. Dealer wants $600 to change the oil, brake fluid, air filter and spark plugs and change collant. I can do most if not all of this. How hard is it to change the spark plugs and what kind of collant should I use? I will be using synthetic oil, most likely M1 5w-30w (when i talked to the dealer they said dino oil would be fine eventhough Subaru service bulletin now says synthetic for all turbo engines) Thanks for any and all info! Robert
If the spark plugs are like my Forester then its not too hard and there are lots of tutorials online.
I would suggest to change your front and rear diff oil as well if not done recently.
The spark plugs are quite easy to access. I don't think I've ever needed any special tools other than a proper spark plug socket, an extension, and a swivel.

You'll likely see varying suggestions on coolant, but the general consensus (which I adhere to on all our Subarus) is to use OEM Subaru coolant. In your case it would be the green "Professional Use Long Life" version. It's concentrated and I create a 50/50 mix with distilled water. I also always add a bottle of the OEM Subaru Cooling System Conditioner (rebadged Holts Radweld), which Subaru also specifies in the owners manual.

I won't make an oil recommendation because everyone has a unique opinion on what's best, but in our Subarus (turbo and N/A) I typically run higher viscosity, HDEOs.
The plugs aren't too bad. Use Subaru coolant with the addative from the dealer.

If you want to use Mobil 1, the 0w-40 or 5w-40 TDT are more appropriate for your turbo setup. Along with a Subaru or Wix filter, change it every 5,000 miles.
Spark plug are easy. A ratchet with a "flex head" does make things a bit easier though.

Air filter is cake

Oil is cake

As far as coolant goes: Use the Subaru stuff. Change it every 30K, change your oil often. Both of those contribute to the head gasket failures.

Coolant on this is pretty simple. Crack open the drain cock in the passenger side of the radiator. Let it drain out. While you're in there, pop off the lower radiator hose where it goes into the block and replace the thermostat with a genuine Subaru part. You'll get a bit more coolant out that way. Put back together, fill with distilled water, run the car until the fans turn on, shut it off, drain again, fill with coolant, burp it, done. Not sure where you live, but if it doesn't get terribly hot in the summers I like to use 60% coolant 40% distilled water. More lubrication for the water pump, more corrosion protection.

Note that Subaru coolant comes in 2 flavors: Pre diluted and full strength. Make note of which one you get and adjust accordingly.

Capacity on mine was 7.4qts plus about another for the overflow
If you read up on WRX and Legacy boards about Mobil1 5W30, you'd probably steer clear of it. Subaru has put in owners manuals that use of a higher viscosity in certain conditions is advisable. You should use Mobil1 0W40 in my opinion.

Be religious about checking your oil on this car.

Don't be another turbo Subaru owner who spins a rod bearing.

And you should use the proper oil filter.
Subaru has a high bypass spec which many after market filters don't meet for this application.
Wix makes a proper oil filter. The popular and proper coolant for this engine is Peak Global Lifetime.

One of a few coolants that meets Subaru's confusingly worded requirements.

Do your research.
Originally Posted By: Nitrofan1
Belt. Get the kit with water pump. The belt isn't the weak link on Subarus, The idler pulley is.

Yes, this too.
I agree with everybody. Grab a gallon of the OEM coolant so drain and fill. Also, you might want to consider draining and filling the AWD axles. Might not have ever been done and would be worth it. A quality synthetic. Check your owner's manual to find out the grade
Thanks for all the info! i will really consider the 0w-40w. in some places I have read use synthetic Rotella 5w-40w. Any thoughts on that...I am not married to any one brand of oil, just want good oil that will stand up to the demands of the turbo. Wont be hotroding it but still turbos have heat issues which i just dont think a dino oil will stand up to. This is a friends car and she knows little about maintaining a car!
Plugs aren't bad. Coil on plug design I believe. You'll want NGK plugs.

Coolant: OEM Subaru.

Oil: M1 0w40 and T6 5w40 are highly regarded in the turbo Subaru community. OEM filter or Wix 57712 would be my choices.

It is coming up on the timing belt service by age. I'd recommend the Gates kit without the waterpump. Get a Subaru one, it's a better quality than the one that comes with the Gates kit. I'd also go Subaru fro crank and cam seals if they are changed at that time. should be of help too. Also as the chassis is the same.
Change front and rear differential fluid. You will need a special big Torx bit (T-70). I bought mine from Amazon for a few dollars. I also used Redline 75w90 for the front and rear differentials.

I'd do a few drain and fills using Subaru HP-ATF. It's easy to change on these cars. It's pretty reasonable at the dealership. The power steering pump uses this fluid as well. 3-5 Drain and Fills on the reservoir isn't going to hurt anything here.

This is my first year owning the 2009 Forester, but I ran M1 5w40 TDT in it this summer. I just drained it and put GC in it for this winter. For an oil filter, I've been running Napa Platinum 41365's on it so far.

I'm not 100% sure, but I think I'll drive my Forester until the 90k mile mark, and then have the dealer do the plugs, wires, coolant, water pump, timing belt, etc.
Save yourself about $450 and do it yourself. Take the savings and go buy a toy or take the wife out to eat; you'll both be happy.

The timing belt can wait till you get closer to 100k miles. No sense in changing it at only 2/3 of it's rated life.
Originally Posted By: rryam
I need some info on a 2006 Subaru Lagacy 2.5L 4 cyl Turbo 70,000 miles. Bought from Carmax and previous owner had service records. Dealer wants $600 to change the oil, brake fluid, air filter and spark plugs……..Robert

Speaking from experience, changing plugs on a flat-4 Turbo in that generation Legacy is going to be a lot more challenging than on an inline 4cyl. There is not a lot of room to work with, between the valve cover and the chassis.
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Don't mess around with aftermarket (especially Prestone and Peak) coolants, unless your goal is to do a chemistry and metallurgical experiment. Use the OE long-life green concentrate. Dilute to 50:50 with distilled water.
On the coolant recommendations, Definitely go with Subaru coolant. If pre-mix is available from dealer use that. I believe some of the contributing factors for the issues were too soft water. I believe distilled would fall into this category. I would say that only Subaru seems to have this issue.

I use premix at shop because storing that much distilled water is a problem, other people in shop would probably just use tap water anyway. The tap water where I work is extremely hard. Would be better off using creek water.

Also the additive is critical.
Blah... Don't use the additive IMO. It's just stop leak... POS. If your car is our of warranty, just use plain coolant and change it often. Shouldn't give you any issues
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