engine oil choice mistake during last oil change, should I change again?

[derolph]

I changed oil and filter in my 88 LX-i on 9/9/16. I have been using 5W-30 oil or 10W-30. After this last change, I realized I mistakenly bought 5W-20 during my last visit to the auto parts store, and this is the oil I used for this last change. We could have some more uncomfortably warm days here in Ohio but temperatures will be gradually getting cooler in the next few months as we progress into, and through, fall. I'm wondering whether I should drain the 5W-20 and replace it with 5W-30, or go ahead and run with the 5W-20 until the next normal change time arrives and then get back to 5W-30 oil or 10W-30, the emphasis being on the 20 vs 30 part of the viscosity rating.

[conozo]

I'm not an expert in oil but i dont think it will matter for you. You live in ohio, it really doesnt get that cold here, 0 or below doesn't really happen often. But i think the biggest reason you are ok is that our engines are very simple, they do not have hydraulic lifters, vtec, or anything hydraulic for that matter.

[gp02a0083]

As Conzo mentioned, i wouldn't worry about viscosity in relation to ambient temperatures. However, being that most of these cars ( with exception of new rebuilds and low milage "barn" finds) will typically have a decent amount of mileage , i would stick to 10w-30 in general. Also don't forget to read up on msds and TDS sheets to make sure the oil your using has a decent amount of metal dopants that put less wear on the valve train.

[derolph]

Also don't forget to read up on msds and TDS sheets to make sure the oil your using has a decent amount of metal dopants that put less wear on the valve train.Eh, I don't know about metal dopants. I've been using Valvoline for a long time and I trust them in their oil formulation. I used their conventional oil until a year or two ago and then started using their synthetic blend. I decided to make that change because the synthetic blend claims to have additives to help reduce leaking from old seals. And, since my car seems to leak a bit at the rear main seal, I thought the synthetic blend would be worth a try.

I've driven about 250 miles now with the 5W-20 oil and haven't noticed anything out of the ordinary with it. But, I'll definitely resume using 5W-30 or 10W-30 the next time I change oil.

[gp02a0083]

Eh, I don't know about metal dopants. I've been using Valvoline for a long time and I trust them in their oil formulation. I used their conventional oil until a year or two ago and then started using their synthetic blend. I decided to make that change because the synthetic blend claims to have additives to help reduce leaking from old seals. And, since my car seems to leak a bit at the rear main seal, I thought the synthetic blend would be worth a try.

Industry standards have changed a lot over the last 6-8 years for oil formulations/blends have had reduction in various metals blended. zinc phosphate is the most popular well known dopant in addition to manganese, and molybdenum. This is why i suggest looking at or obtaining the MSDS and TDS, even the major brands like castrol, penzoil, quaker state, and even valvoline have cut concentrations back to about 800ppm when prior to 6-8 years ago the "same oil" could have had 1000ppm-1200ppm. kinda a big deal when your talking about longevity of a flat tappet valve train. Be careful of oils out there that state they are "synthetic" , a number of them aren't and that's why you see "full-synthetic" on some labels. Not really surprised that switching over to "synthetic" caused more leaks, ive seen this happen a decent amount.

[MessyHonda]

unless the motor was built with tight clearances on the bearings i would not worry so much. you say you have a rear main leak. the purpose of oil is to lubricate not to stop leaks. on my dx it did not like synthetic oil and found the leaks faster.