Should I use heavier weight oil?

[Hendo]

Don't be afraid of a thicker oil, try a xxW40 (xx being whatever number suite your min temp in your area) . Your veichle has so many miles that the bearing clearances will be looser than stock.
Hddeo oils usually have fantastic add packs, rotella t6 or m1 TDT would work well, and have a high flash point and low noack so less burn off.

 

[Merkava_4]

Originally Posted By: Hendo
Don't be afraid of a thicker oil, try a xxW40 (xx being whatever number suite your min temp in your area) . Your veichle has so many miles that the bearing clearances will be looser than stock.
Hddeo oils usually have fantastic add packs, rotella t6 or m1 TDT would work well, and have a high flash point and low noack so less burn off.


I had two jars in my refrigerator for 24 hours. One jar with 10W-30 and the other jar with 10W-40. Both oils measured 39*F with a digital thermometer. I did this because I couldn't make up my mind which oil to go with for the upcoming winter. The 10W-30 looks plenty thick at 30*F, but the 10W-40 was ... dare I say ... a little too thick to flow quickly at that temperature. I haven't tried any 5W-40 in my refrigerator yet, but I'm guessing it would be thinner at 39*F than the 10W-40 is. Now in the summertime, when the ambient temps are at 100F, the 10W-40 flows very well. I was just hesitant to use it for the winter. Typically, Central California has its winters around 40*F during the daytime.

 

[Shannow]

I used a 25W-70 through a winter here some years back (down to -7C), car still started and ran...a bit sluggishly.

 

[Merkava_4]

19*F is about what my freezer is. I put a jar of 10W-40 in there
one time too. That oil is like motor honey at that temperature.

 

[Ramblin Fever]

The 3.2L sohc engine is a very stout, reliable engine; I have one myself in my 97 rodeo, with 205k miles and going strong.

This engine DOES have a PCV valve and is VERY important to it's running right; should be changed every 6mnths, no kidding; but they're cheap and easy to get too.

Mine does not burn or leak oil however; knocking hard on wood.

That said, I had mine on Maxlife 5w-30 for several years, just because that was the oil my sister & I could both use.

However in the last 6 mnths I've since switched to Quaker State Defy 5w-30 - my engine runs a lot smoother, and again, doesn't use any oil, but I like how the Defy is labeled an SL oil for use in older engines.

15w-40 is not too thick for these engines in Australia or if you lived in the Arizona desert; but truthfully, there's no need for an oil this thick and could actually rob the engine of needed lubrication at start-up as well as diminish gas mileage greatly.

10w-40 is not needed either.

5w-40 Rotella diesel/gas oil is considered the jewel among Isuzu owners; great start-up oil without being too thick and has great cleaning properties at a slow rate; has also greatly slowed down oil usage in 90% of the older engines.

 

[Jay1981]

I would try a HM 5w30 first for a couple oci's and if that doesn't help, then try a HM 5w40.