What's the proper oil for a push mower

[440Magnum]

Originally Posted by jayjr1105
I'm just curious what's the actual oil spec you're supposed to use in a typical push mower engine. I always thought PCMO wasn't that great for mowers because it holds all the dirt in suspension where a filter would normally clean it out but with no filters on a typical push mower engine, what's the actual proper oil to use?


The owners manual will say, but it's been decades since I've seen any recommendation other than SAE 30 or 10w30 with any PCMO spec newer than about SG.

That said, being in a hotter climate, I run Rotella T6 5w40 in all my OPE, and have for 20 years. That includes 2x 6-ft-lb B&S vertical shaft side-valve engines, a 1970s 5-horse B&S horizontal shaft side-valve tiller engine, a 15-horse circa 1990 Kohler lawn tractor OHV, and a 2014 28-HP B&S v-twin ZTR mower engine that has about 500 hours. Zero issues, zero oil consumption.

 

[CharlieJ]

I've used everything from 5w-30 to 20w-50 in mowers and the mower never cared. But, this is Florida and mower use is only when it's warmer so no cold starting. I currently have a blend of 15w-40 and left over 5w-30 from car oil changes, works great!

"It's a lawn mower, not the space shuttle!" - Taryl Dactal

 

[IMSA_Racing_Fan]

My lawnmower is a neglected hand me down Honda that smokes like crazy for the first 10 minutes then stops so I pour in 15W-40. I works so I keep using it. Maybe the smoking doubles as a mosquito repellent.

 

[IMSA_Racing_Fan]

This thread just reminded me its time to mow the backyard,

Here I go start your engines

 

[Oildudeny]

Latest spec detergent oil usually a hd30,, 10w30 or newer Briggs say a synthetic 5w30

 

[53' Stude]

Originally Posted by ARCOgraphite
Any thing leftover from you car**: keeping gas clean and blade sharp and balanced is more important. Add to that Cleaning and oiling the air filter.

**But NO 20 grade or 50 grade but anything in between is fine.

Go to for ODPE was 10W30 Rotella Triple Protect dino.

I think you can only get this in bulk now, not in gallon jugs.

All my equipment HATED T5 10w30 semi synth. - Or at least what they blended 3 years ago.

Your engine will outlast the rest of the mower. My 3.5hp briggs Yard Machines was purchased in 1991 and is still going strong except wheels, and bags are falling apart. That got an OC maybe every 3 years or so.



Arco: I can get rotella 10w30 HDEO in gallons at Rural King

 

[AnthemBassMan]

Originally Posted by Rmay635703

I had an old 2 cycle that called for non-detergent.

My guess is ancient machinery might spec it for lack of anything better existing at that time


That was so the plug wouldn't foul out from the detergents in the oil. I think Lawn Boy used to specify using either a 20 or 30 weight non detergent oil to mix with the gas.

L8R,
Matt

 

[ARCOgraphite]

Originally Posted by 53' Stude



Arco: I can get rotella 10w30 HDEO in gallons at Rural King


Good to hear its available. thats T4?

I dont have Rural Kings around here, but the SANEL: auto Parts may have it.

They just merged with NAPA so it might be time for a drive and see whats cookin!

thx - Ken

 

[OilReport99]

T4 10W-30.

 

[vw7674]

Mine starts easier with 10W-30.(priming bulb & two tugs) Straight 30W not so much. : l

 

[TheLawnRanger]

I've always used HD 30 until this year. I'm currently using full synthetic 5w30 since I have a bunch in the oil stash. No difference so far.

 

[ZebRuaj]

I purposefully picked up a couple jugs of RGT 5w30 with the Autozone clearance and Shell rebate in preparation for the mowers I usually pick up on the curb and flip.

 

[spasm3]

Currently running 15w 40 of various brands in my zero turn, and in my lawn boy briggs engine. Works great.

 

[oldhp]

Just put in QS conventional 10W40, new plug, cleaned air filter and sharpened the blade. I'm ready.
This mower has had everything from 0W20 to 20W50 Harley oil. It's at least 15yrs old. Replaced the carb once.

 

[Silverado12]

FWIW I have used both Rotella T-5 10W-30 and full syn 5W-30. The 5W-30 seems to hold up better as it doesn't drain out as thin as the 10W-30.

 

[GMBoy]

I have always and still do run Mobil 1 synthetic oil in all my OPE. Either 5w/30 or 10w/30.

 

[4WD]

I like 5w30 synthetic in pull start
10w30 Delo or 15w40 Delvac in rider

 

[Triple_Se7en]

Originally Posted by jayjr1105
I'm just curious what's the actual oil spec you're supposed to use in a typical push mower engine. I always thought PCMO wasn't that great for mowers because it holds all the dirt in suspension where a filter would normally clean it out but with no filters on a typical push mower engine, what's the actual proper oil to use?

Rotella T6 5W40 Synthetic

 

[zzyzzx]

Using straight 30 weight, but in the process of switching to synthetic 5W-30.

 

[4WD]

Should be a short process