Differences SAE 30 weight oil ratings SM or SL

[padus]

Hi,

I have a Lawnboy lawnmower that I'm running with WM Supertech 30 weight that is API SM. The first season I ran it with the LB Premium 4-cycle oil that had more of the older API ratings on it.

I saw also that Castrol HD30 has the API SM. BUt Pennzoil does not have API SM.

My question is: Is the SM rating bad because I read here that some users don't like zinc in there oil?

I'm a bit confused with this SM and zinc stuff.


Thanks,

 

[Quattro Pete]

Actually, SM oils have a weaker additive package, but either SM or SL should work fine in your mower. I use Pennzoil HD30 in my Toro with B&S engine.

 

[Robenstein]

If it is a PCMO straight weight oil, then SM will mean less zinc than SL. However, the straight weight Diesel oils that are SL or SM will still have higher zinc. I would just get some Rotella SAE30 and stop worrying. I put Mystik diesel oil in mine and it runs great.

 

[odie]

picked up 2 quarts of the PENNZOIL HD SAE 30 that's SL for the 1st oil change of the BOLENS 13.5 H.P. ( B+S ) riding mower for $3.47 a quart . Plan on using PENNZOIL Platinum 10w-30 for the 3rd oil change and possibly there after . Good idea ? Thanks

 

[Robenstein]

Platinum does not have enough zinc IMHO. Id stick with HD 30 or Rotella SAE30 to get optimal protection from a SOPUS product.

 

[Superbuick96]

Im using PYB HD 30 too

 

[padus]

What do you Guys think about Walmart's supertech lawmower sae30 ?

 

[kbowley]

I have seen nothing bad in the uoa thread with the super tech, its a good quality oil as well as solid well built filters. The api rating is what to look for over brand. check the bottle for a rating of SL as it has a better add pack for flat tappets as well as the 450 degree temps at the bottom of the piston crown that small engines produce. I personally use HD30 Castrol, valvoline, and store brands that have the SL rating. If i visit the dealer, i pick up some Kohler oil as it is very stout stuff. In the winter i use Amsoil 4 cycle 10w-30/30w as it is also very stout and is a straight 30 base that has a pour point that qualifies it for the 10w rating. it uses no viscosity improvers.

 

[Hitzy]

Originally Posted By: padus
What do you Guys think about Walmart's supertech lawmower sae30 ?




The best deal going for us Canucks for lawnmower/OPE oil is the Supertech 15w40 diesel oil. It's CI/SL rated and $8.50 for a 4L jug. They have a "premium diesel" as well that is CJ/SM rated, but the basic CI/SL diesel is the better oil in my opinion.

 

[sweezy722]

I really like the looks of the Super Tech Universal Oil. I believe it is HDEO and 30 wt. It is rated SJ, CF, CF2. For 2 gallons it is about $19.00.

 

[JimPghPA]

Padus,

Multi-grade oils like 10W-30 have the molecules shear, break down, and loose viscosity quicker in air cooled engines. You are probably better off to stay away from multi-grade oils unless you are going to run it in the winter. If you are going to use a mulit-grade, a full synthetic will hold up better than a dino.

Many people here on BITOG like GC for air cooled engines. It is almost a 40 weight, and being a true synthetic it holds up well in air cooled engines.

 

[heavyhitter]

I would say that a 15w40 HDEO oil would be a good substitute for a straight 30wt oil in a small engine.