Dumb Mistake

I changed to synthetic oil in my 2009 4 cyl PreRunner according to specifications it requires SAE 5w-20 or 0w-20. I made the mistake of looking at the bottom of the page at the specifications of the V6 which, ask for 5w-30. Is there in any problem with running 5w-30 for 3000 miles and then swapping it or should i take a loss and dump the oil and purchase 5w-20 or 0w-20?

 

Man does it really call for 5W-20? I had a hard time convincing myself to go from 10W-30 to 5W-30 in the 07 4.0. If I were you I would stay with the 5W-30 bro.

 

I'd stay it should be fine.

 

5w30 is fine....absolutely fine. with the 5w20....you supposedly get a tiny bit better mileage, but i still think 5w30 protects better.

 

The original spec on the engine was 5-30(from what I read at TN). Then it switched to 5-20 or 0-20. I suspect the engineers determined that the variable timing works better with the lighter oil. I’d switch it out to the correct spec. The cost is nothing compared to what you spent on your new truck.

 

u should be fine. i had a 99'taco with a 2.7 and back then toyota recomended 5-30 only now do they tell u to use the 5-20 for fuel reasons

 

Brand new engines with close tolerances can use very thin oils. As componants wear though I think you guys wll all be switching to thicker oils like 10w-30 and 10w-40.

 

I just got my truck back from getting the timeing cover TSB completed, among other things, and the dealer put in 5w30 Mobile 1 synthetic. So I would assume 5w30 is fine.

 

We are talking about the I4 not the V6

 

OK... I knew that, but slipped my mind from the time I read the post and when I was able t oreply... pretty busy at work today. BUT.. their is no real diffrence

 

Maybe, but actuation better be based on a position sensor and not the viscosity of the oil. Absolute viscosity changes with temperature widely.

I think they spec 5w-20 because the 4cyl. engine is smaller and therefore can be made to hold tighter tolerances tan the V6, plus it's more focused on economy. Remember that because of CAFE standards, auto makers have to get the max possible economy out of a large volume of tiddlers, so theyt can sell a handful of high profit luxury vehicles with poor economy.

(OK, in truth I don't know if they ever applied that law to light trucks, but that 4-banger is in the Camry too, right?)

 

The 4.0 has the same VVT as the 2.7.... I honestly think we are at about the same point in this conversation as we would be if we were talking about different oil brands. There are some good points being made like better economy requiring closer tolerances, and therefore thinner oils. But if that helps the smaller engine produce more efficiently, then would it not do the same for the larger engine? If we eliminate the VVT system, thicker oils, up to a point, WILL produce better protection by providing a thicker cushion. The VVT systems are designed to work on pressure transfer, and pressure is built by volume. Thicker oils will have lower flow, so slower response to pressure requirements. So, theoretically, thicker oil will produce a performance "Lag" when kicking in, as well as a "Lag" in reducing that performance back to an economical mode. Therefore... thicker oil COULD reduce gas mileage.

Does that make since? Other than all of my crappy spelling...

 

Well... I guess 'same' is a huge statement. The function of the VVT system in similar years of toyotas is identical. The way it is implimented, and thus tuned would most definately be different. Toyota isnt going to recreate the the wheel every time they build an engine. I cant think of a reason for one engine to use a diffrent oil at all. I canimagine that a VVT engine could specifically not use synthetic oils, since the molecules in synthetics are smaller, causing pressure bleedoff. But... Ive never seen that stipulation.

 

No doubt that thicker oils will reduce gas mileage as long as you're comparing identical engines with identical wear.

As for the VVt reqt's. I'll have to look into that. I really don't know much about the system other than the theory of why it works. Certainly nothing about the technique of how it works.

Also I did not mean the the I4 was made to closer tolerances than the V6 (though it might be) but that the shape and size of the I4 engine contributes to its maintaining those tolerances better than the V6 as it heats up and cools down.