[wyoming saab]

and was just curious what you guys recommend for oil and fuel. I used power premium in my 1994 900se, but noticed some stalling and extraneous rattles. Switched back to 85 octane and it all stopped. Just wanted to know if the power premium would be better. Also curious if fully synth would benefit me more in terms of motor longevity. A local mechanic told me to only use fully synth in H.O. motors. Thought I would ask you saab experts for advice. Thanks.

 

[Kermit]

Use standard fuel if standard car, switch to premium if you mod the engine. We recommend fully synth oil, Mobil 1 seems to be the most popular. (Saab service intervals are 12k, but we recommend a change every 6k to prevent sludging problems).

 

[course9x]

Kermits,


So since I have a 2000 9-5 (regular), I should use 87 octane (regular)????

Dave

 

[Kermit]

Yep, only Aero's or modded cars should be on premium. It won't harm running on premium but why spend extra when you could be saving for that ECU upgrade.:cheesy:

 

[Raven18940]

While it will run on 87, Saab recommends AON 90 for optimum performance. I'd run it on mid-grade at least anyway, I wouldn't put 87 in my lawn mower. It's complete junk, my jeep used to ping in warm summer days and it had an 8.8 - 1 compression ratio. And this wasn't Discount Dan gas, it was Mobil-Exxon. Spend the extra $1.50 and give your car mid-grade.

 

[Mattlach]

Essentially a good rule of thumb is as follows:

Use whatever gas is recommended in your cars manual. For relatively new saab turos I believe this is premium (93 oct (ron+mon)/2 ) but I could be wrong. it is premium for my Aero. For most NA cars it is regular (87 (mon+ron)/2 ).

If you get higher octane gas you are just wasting your money, if you get lower octane gas your performance will suffer and you might damage your engine.

The only time it makes sense to go up in octane is if you have tuned the car...

I wouldn't put 87 in my lawn mower. It's complete junk, my jeep used to ping in warm summer days and it had an 8.8 - 1 compression ratio. And this wasn't Discount Dan gas, it was Mobil-Exxon. Spend the extra $1.50 and give your car mid-grade.

Sometimes cars ping on the octane gas they arte designed for becasue they are worn or in need of a tune-up. In these cases using a higher octane gas can mask the problem, but it is better to have the actual problem fixed, than wasting your money by going up in octane.

 

[course9x]

So is 89 the optimum, or 91?? Since the book says 90.

Dave

 

[Mattlach]

So is 89 the optimum, or 91?? Since the book says 90.

Dave

Just becasue I'm a stickler for the rules, I would in your case use 91 octane gas. (thats an unusual octan rasting though? Everhwere I go have 87,89 & 93)

It is unlikely you will damage your engine by running lower, as our cars - like most other - have knock sensors that will slow down the timing to avoid a knock.. So your engine will be protected, but possibly at a slight and sometimes noticeable loss in power and acceleration, - to quote the article posted below.

In your case I might run 89 octane when its cool out, and switch to 91 during hotter days... As it stands for me I currently use premium all the time as thats what my manual suggests.

To read up more on it this is a good starting point.