The 98 is a phase one engine and I didn't realize the TB change interval was 60K. My 2000 is a phase two engine and the TB change is 105,000. My mistake. Ed
Just put AMSOIL 5W30 in my 1998 Subaru Forester.
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That's a software "feature" in the control unit. It's probably eager to downshift into 3rd when you apply the brakes sometimes, too.
Check for stuck brake calipers, to correct the bad MPG.
Im using M1 ATF in a Legacy with no problems.
I don't think 10k miles would be too long for that vehicle.
For the trans issue, make sure the ATF level is correct. It may just need fresh ATF, even if you use dino. It just needs a Dexron II/III ATF. From the drain plug though you will only get about half the ATF out, so you need to do multiple changes, or unhook a line from the radiator cooler and pump and dump the old out.
Also, you really should measure your tire circumferences and make sure they are all within 1/4" circumference. If they're not, this can cause damage over time to the transfer clutch in the rear extension housing of the AT, and could be contributing to your lowish mileage. Also front o2 sensor (OEM only!) might help, as could a general tuneup and seafoaming if it hasn't had it recently. Subaru's, especially of this era really like NGK spark plugs and OEM plug wires.
I would not hesitate to switch to the amsoil syn ATF in that vehicle. I have changed over three Subaru's at ~100k miles and they all love the fluid.
Don't neglect your front and rear diff gear oils.
I've run the amsoil HDD 5W-30 for 18,000 mile intervals in a '96 Subaru with good results.
Keep an eye on your coolant overflow tank for any bubbling or milky yucky junk in there.
For the trans issue, make sure the ATF level is correct. It may just need fresh ATF, even if you use dino. It just needs a Dexron II/III ATF. From the drain plug though you will only get about half the ATF out, so you need to do multiple changes, or unhook a line from the radiator cooler and pump and dump the old out.
Also, you really should measure your tire circumferences and make sure they are all within 1/4" circumference. If they're not, this can cause damage over time to the transfer clutch in the rear extension housing of the AT, and could be contributing to your lowish mileage. Also front o2 sensor (OEM only!) might help, as could a general tuneup and seafoaming if it hasn't had it recently. Subaru's, especially of this era really like NGK spark plugs and OEM plug wires.
I would not hesitate to switch to the amsoil syn ATF in that vehicle. I have changed over three Subaru's at ~100k miles and they all love the fluid.
Don't neglect your front and rear diff gear oils.
I've run the amsoil HDD 5W-30 for 18,000 mile intervals in a '96 Subaru with good results.
Keep an eye on your coolant overflow tank for any bubbling or milky yucky junk in there.
I would not go much over 7500 on ASL oil without doing a UOA. You need to know if anything is going on before extending it to 10K. Amsoil ASL is great oil, but using it for extended oil changes is only for cars with nothing wrong.
As for your AT, you need to ask about the history of fluid changes and look at the color of the fluid on the dipstick. Drop some on some white paper or a white coffee filter. Unless its really red (not dark red) the fluid should be changed. If you cannot determine if the pan or filter were done, they should be done also. You can then decide whether to go to Amsoil ATF or stick with the normal stuff. Amsoil ATF introduced properly into an AT will never cause a problem. That is where looking at the filter and how much crud is in the pan is critical.
As for your AT, you need to ask about the history of fluid changes and look at the color of the fluid on the dipstick. Drop some on some white paper or a white coffee filter. Unless its really red (not dark red) the fluid should be changed. If you cannot determine if the pan or filter were done, they should be done also. You can then decide whether to go to Amsoil ATF or stick with the normal stuff. Amsoil ATF introduced properly into an AT will never cause a problem. That is where looking at the filter and how much crud is in the pan is critical.
Like Pocupine73 said, don't neglect front and rear diffential gear oils. Change that over to synthetic such as Amsoil Severe Duty and you may see a gas mileage increase. Chnage the plugs and wires with oem if you have not yet done so.
I've also heard good things about Maxlife Transmission fluid and it curing harshg shifting. It is less expensive than Amsoil and is a synthetic blend.
I've also heard good things about Maxlife Transmission fluid and it curing harshg shifting. It is less expensive than Amsoil and is a synthetic blend.
Ive heard good reviews about Lube Guard Red additive for automatics.
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I would not go over 5K without a UOA on that high mileage engine. You could have fuel or coolant dilution concerns. Sometimes switching to synthetics isn't worthwhile overall. Sometimes those 3-4K dino OCIs are best for minimizing dilution problems - when not able to fix the problem due to lack of monetary funds.
I just recently changed the front and rear diffs to Mobil 1 75W90 syn ... made a big difference. Before, I'd get a bit of a shudder or bucking motion when I'd leave off the gas and then again when I accelerated. The Mobil 1 stopped it completely - amazing.
I thought that the front diff. in a subaru was fed by the transmission oil??? I replaced my rear diff with AMSOIL synthetic- can I replace the front or is that the tranny fluid?
I had the tranny fluid replaced by the dealer at 115,000 miles. I am not sure if and/or when it was replaced in the history of the car. For all I know it may have never been replaced. I had them use regular old tranny fluid and they did the total replacment not just a simple drain and fill.
For now I am goign to leave teh tranny alone. I figure wit hthe new fluid I should have 30K miles before needign to replace it again and hopefully it will nto break in that time but something is definitly not right with it. However it still drives.
It jsut does nto go thru the gears 1-2 and 2-3 smooth. There is a hickup between gears where the next gear does nto grab at the right tiem and then it does the car jearks a bit.
Who knows. At this point I think I just drive it and keep a watchfull eye. I could take it to AAMCO or MIDUS to get the transmission looked at but I am nto sure if it is worth it- what will they be able to do???
In manual transmissions, yes, the gear oil for the front diff is shared with the transmission. For automatic transmissions, the front differential has a separate GL-5 gear oil; it does not share the ATF (because it is hypoid style differential; it is not a transverse mount like most FWD transaxles).
I would stay away from aamco. You would need to find a known honest reliable trans shop which can be difficult. Ideally they should be familiar with Subaru or Japanese or import vehicles.
Hi. For the front diff, if it is an automatic transmission, the drain plug is underneath the vehicle, under the front diff. It can a little hard to spot at first. IIRC it takes a 22mm or optionally 7/8" socket. Also there is a copper sealing washer that should be replaced.
Then after putting the drain plug back in, you refill it through the dipstick hole. It's a yellow handled dipstick, near the firewall, in the middle but slightly on the RH (passenger) side. I'll see if I have any pics of this...
Also there are several good Subaru specific boards for Subaru maintenance and stuff, including www.subaruforester.org www.ultimatesubaru.org www.subaruoutback.org www.scoobymods.com and others
Then after putting the drain plug back in, you refill it through the dipstick hole. It's a yellow handled dipstick, near the firewall, in the middle but slightly on the RH (passenger) side. I'll see if I have any pics of this...
Also there are several good Subaru specific boards for Subaru maintenance and stuff, including www.subaruforester.org www.ultimatesubaru.org www.subaruoutback.org www.scoobymods.com and others
Wanted to give a really late update on this. not long after chaning he oil the gasket (head) started leaking and air got into the coolant and the car overehated. I never wanted to pay to get the seals replaced so the car became a lawn ornamant for the past 9 years. Really sucks - I attribute it to the synthetic oil.
Originally Posted By: jasno999
Wanted to give a really late update on this. not long after chaning he oil the gasket (head) started leaking and air got into the coolant and the car overehated. I never wanted to pay to get the seals replaced so the car became a lawn ornamant for the past 9 years. Really sucks - I attribute it to the synthetic oil.
Subaru has a know issue with head gaskets on the 2.5l engines and it has nothing to do with oil.
Wanted to give a really late update on this. not long after chaning he oil the gasket (head) started leaking and air got into the coolant and the car overehated. I never wanted to pay to get the seals replaced so the car became a lawn ornamant for the past 9 years. Really sucks - I attribute it to the synthetic oil.
Subaru has a know issue with head gaskets on the 2.5l engines and it has nothing to do with oil.
Originally Posted By: jasno999
Wanted to give a really late update on this. not long after chaning he oil the gasket (head) started leaking and air got into the coolant and the car overehated. I never wanted to pay to get the seals replaced so the car became a lawn ornamant for the past 9 years. Really sucks - I attribute it to the synthetic oil.
Any chance this was related to flushing an old engine?
Wanted to give a really late update on this. not long after chaning he oil the gasket (head) started leaking and air got into the coolant and the car overehated. I never wanted to pay to get the seals replaced so the car became a lawn ornamant for the past 9 years. Really sucks - I attribute it to the synthetic oil.
Any chance this was related to flushing an old engine?
Originally Posted By: Surestick
Originally Posted By: jasno999
Wanted to give a really late update on this. not long after chaning he oil the gasket (head) started leaking and air got into the coolant and the car overehated. I never wanted to pay to get the seals replaced so the car became a lawn ornamant for the past 9 years. Really sucks - I attribute it to the synthetic oil.
Subaru has a know issue with head gaskets on the 2.5l engines and it has nothing to do with oil.
I agree
I had my head gaskets go at 80k miles on a 2010 Forester.
Originally Posted By: jasno999
Wanted to give a really late update on this. not long after chaning he oil the gasket (head) started leaking and air got into the coolant and the car overehated. I never wanted to pay to get the seals replaced so the car became a lawn ornamant for the past 9 years. Really sucks - I attribute it to the synthetic oil.
Subaru has a know issue with head gaskets on the 2.5l engines and it has nothing to do with oil.
I agree
I had my head gaskets go at 80k miles on a 2010 Forester.
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No, there is no way oil, or a flush did this. Phase 1 and early Phase 2 SOHCs had horrible issues with HG's. Subaru did not roll out the official fix until I believe 2003. They need to be replaced with either Six Star or Cometic brand or you will be doing the head gaskets again.
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Originally Posted By: jasno999
Wanted to give a really late update on this. not long after chaning he oil the gasket (head) started leaking and air got into the coolant and the car overehated. I never wanted to pay to get the seals replaced so the car became a lawn ornamant for the past 9 years. Really sucks - I attribute it to the synthetic oil.
You had a head gasket leak (combustion products into the cooling system) and you attribute it to the motor oil being used?
Wanted to give a really late update on this. not long after chaning he oil the gasket (head) started leaking and air got into the coolant and the car overehated. I never wanted to pay to get the seals replaced so the car became a lawn ornamant for the past 9 years. Really sucks - I attribute it to the synthetic oil.
You had a head gasket leak (combustion products into the cooling system) and you attribute it to the motor oil being used?
That's like saying the wheel fell off because he put gas in the tank.
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