Is It Ok To Use 5W30 Regular Oil In A 1990 350 Tbi?

[Joe In Montana]

OK.... time for some real scienterrific intelligence here I can see.

I've solved the mulitweight low viscosity problem by a formula that I use all the time.

2.125 quarts of Castrol 10-30 GTX
1.625 quarts of Castrol 30 GTX
1 quart of Castrol 50 GTX
1/2 quart of Lucas Break In Additive.

I mix this up in 55 gallon batches, more as a hedge against inflation or for the next petroleum shortage.....which is coming.

That gives me Castrol 20/50, more or less, which my two engines with flat tappets require, and the ZDDP in the LUCAS makes it all good.

The 0.750 extra oil is for the 1 quart filter.

 

[100 MPH speedometer]

I made a mistake a put in tje wrong oil the other day. 5w30 regular oil which i usually use 10w40 regular oil.

I out a new filter on too.

I stay in new orleans and it does get cold so im wondering if it will be okay with a 5w30 oil until next oil change

5W30 is for where temperatures are regularly below 20. 10W30 is more for temperatures above 20 and a perfect oil for New Orleans is 10W40. 20W50 is for temperatures above 100. That oil will evaporate faster because it's too warm outside.

http://www.machinerylubrication.com/Read/30197/choose-engine-oil

 

[campfire]

And we've run 10-30 in Iowa all my life and it gets below zero for months sometimes in the winter.

Where abouts in Iowa?

 

[rayfin]

Where abouts in Iowa?

Sioux city

 

[campfire]

Sioux city

Cool. There are a number of active club members in that general area.

 

[rayfin]

Cool. There are a number of active club members in that general area.

And I have an auto/boat upholstery shop.

 

[Mastiff]

My newer Jeep manual says 5w20, which seems way thin, especially here in Tucson where it seldom gets below 40. I don't know if the engines really want this watery stuff, or if the manufacturers spec it so they can squeeze a few MPG more out for the feds. I've been using 5w30 instead, but may go higher on the low side once the warranty is fully run out.

Although, I've never really understood why 0w100 (whatever you can find with the smallest left number and highest right number) wouldn't always be better, based on the superficial explanations of multiweight oil that I've read.

 

[diesel4me]

I've read that multi-weight oils have a lot more additives that can gel up or create sludge,and that straight weight oils are actually better lubricants--but the fact you'd have to be swapping out to a different viscosity every time the temperatures changed led to the development of multi-weights...

While I think newer engines made with tighter tolerances "need" thinner oil,after you put 50,000 or more miles on an engine,they should have "loosened up" enough not to be affected much by using a thicker oil...a lot of guys I know put 10W-30 in everything once the engines accumulate higher miles and they haven't spun any bearings or tossed any rods...yet !....

 

[Joe In Montana]

I can paraphrase the idea, but here's a good read on the 0w-20 lube oils from Babcock Tech Group.

 

[campfire]

I've read that multi-weight oils have a lot more additives that can gel up or create sludge,and that straight weight oils are actually better lubricants--but the fact you'd have to be swapping out to a different viscosity every time the temperatures changed led to the development of multi-weights...

While I think newer engines made with tighter tolerances "need" thinner oil,after you put 50,000 or more miles on an engine,they should have "loosened up" enough not to be affected much by using a thicker oil...a lot of guys I know put 10W-30 in everything once the engines accumulate higher miles and they haven't spun any bearings or tossed any rods...yet !....

Being in a cold region, my philosophy is to run the recommended light-weight oil for as long as I can and then gradually increase the viscosity as the engine gets older and starts leaking and/or burning oil internally. So far I've only owned one engine that didn't consume oil, the others have all gotten some form of thicker oil or Lucas oil stabilizer. HD30 oil is actually on the list of approved summertime oils for my 6.2 engine, though I haven't seen it recommended for newer engines.

I can't measure whether or not the Lucas additive increases lubrication, but I have found that it slows down leakage rates.

 

[4xcrazy]

I've read that multi-weight oils have a lot more additives that can gel up or create sludge,and that straight weight oils are actually better lubricants--but the fact you'd have to be swapping out to a different viscosity every time the temperatures changed led to the development of multi-weights...

While I think newer engines made with tighter tolerances "need" thinner oil,after you put 50,000 or more miles on an engine,they should have "loosened up" enough not to be affected much by using a thicker oil...a lot of guys I know put 10W-30 in everything once the engines accumulate higher miles and they haven't spun any bearings or tossed any rods...yet !....

Thats where full synthetic oils are supposed to come in, they're not supposed to have the trouble of sludging over time, supposed to last longer, not break down as soon as conventional oil as well.