What weight oil do you guys use?

[davege]

The Owners manual and oil filler cap on the TTA recommends using 10-30 wt oil. Has anybody used a synthetic 5-30 instead? Are their any blow-by issues?

I am due for an oild change and was interested in different perspectives on this.

Thanks,
Dave

 

[1badTTA]

Hell, I have used a 0W30 synthetic oil and had no problems, really doesn't matter too much. Only reason I would change to a different viscosity is due to oil pressure changes due to change of weather or loose bearings. I live in Arizona so any oil will work fine since I have about 30+psi at a hot idle.

I generally use Dino oil, Valvoline 5W30 or 10W30 and change it about every 2500 miles or if the car runs rich or I go racing or if I go through emisions or if Jupiter, Mars, and Pluto line up.

As long as you have good oil pressure, use the lightest oil you can get away with, It will provide the fastest startup lubrication and also free up a couple extra HP's

 

[89ICBM]

Hi,

I'd like to make a few comments on this. Unless you have a fresh rebuilt motor and are adding oil to it, you should never change brand or weights. Any engine builder will tell you, decide on the oil you will use from the start and stay with it. Why, you ask, because when you change brands, you are just playing chemist. Different brands have different additives and they are not all compatable. I will ask, do you know what the W stands for in 10W30? The W stands for winter (10 weight winter, 30 weight summer). If you live in the north where you have exteme winters and drive your car in these conditions, you need the multivisc, if you don't drive in these conditions, it's useless. I am not a fan of synthetics in a turbo car for 2 reasons; 1st, if you change your oil every 2500 to 3000 there is simply no need for it, 2nd; synthetics do to it's molecular structure, does not hold additives, another words, the additives seperate. Mobile claims they have solved that problem but hey, they're trying to sell oil. You are better off if you live in warmer climates or only drive in the summer, going with a straight 30 weight, high detergent oil and change it regularly. If you know the brand that is in the car before you change, use the same brand. HTH

 

[Razor]

I never go by mileage, I go by filth. If I pull the dipstick out and its dirty, it gets changed. Dont care if its 300 miles or 2K miles.

Another tidbit, I was on the phone with my Cam MFG and they recommend not using synthetic oil due to it being veryslippery and possibly not letting the lifter turn in its bore as the cam goes around. So here is another strike against synthetics.

valvoline 20W50 in mine.. cuase it was on sale.

 

[89ICBM]

Razor,

I agree strongly on both points you made especilly the 'when it's dirty, change it' point. I have discussed this issue in length with lubrication engineers. What is recommended for a daily driver is to use a marine 'hour run time' gage and change the oil every 50 hours, not by mileage. For our cars, your method is even better, keep fresh oil in it. Now, having said that, I will add another point about multivisc oil. The additives that are used to make an oil multivisc are the very culprits that cause coking in the turbo bearing, this includes synthetics.

As far as Davege's initial question, I hope I answered it in my 1st post. If not, then I'll say this; don't use a synthetic, save your money for something else; do use the same brand that you have in it now and stick with that; don't use a multivisc, unless, you live in a climate that requires it, say, like the Arctic! Only kiddin.

 

[RobR]

I will still use my Mobil 1 10W30. I've seen what the inside of engines look like with it and am very impressed with how clean everything was. My Spirit R/T had 80K miles on it when the intermediate shaft broke, it turns the oil pump. I drove 3 miles with no oil pressure. Got it home and dropped the pan. Very impressed with what I saw. Everything was spotless. The balance shaft casing still had the original handwriting on it and the aluminum was bright. Pulled the bearings and they were still perfect. Cross hatch looked like it was just done.

I like to see what conventional oil would do in a situation like that.

 

[TTA850]

I've seen what a synthetic oil will do in a high stress area, especially one with poor oil flow/lubrication like parts of our motors and it's not good. Seen a friends big mopar rocker shafts turn blue after 6 passes after switching to sythetic, he never had a problem before with conventional and never had a problem again after switching back.

That was one of my main reason for not liking synthetics, and I use Penziol GT 25W50 in my GTA's motor - I dont really remember what I put in my other cars, probrobly a 10W30 or 10W40 Penzoil or Castrol conventional oil.

HTH,
Steve

 

[davege]

Thanks for all of the feedback guys. My cars are stock and have very low miles on them (see signature). They usually see about 100-200 miles per year. I am not the original owner on my cars but it would be my guess they both have been run on 10-30 all of their lives.

- Dave