HDEO good and bad in gasoline engine

[farang]

Saw lots of recommendation about HDEO (such as Delo 400, Delvac 1300) for high mileage gasoline engine for cleaning purpose!

I wonder is there anything that bad for the engine if used HDEO! Beside that, what else does HDEO do to a gasoline engine?

The cars in question are 91 and 95 Honda Accord! Both recommend 5w30 but most HDEO are 15w40. I am in LA.

Please advise!

 

[ekpolk]

I have no experience using HDEOs in gas engines. With that in mind, I do recall that Redline used to caution against using their diesel oil in gas engines because of the possibility of plug fouling resulting from the greater amounts of detergents in the HDEO. I don't know if this was Redline-specific, but it has always kept me thinking when I've seen these discussions here at BITOG. On the other hand, I have not heard any of our members report this actually happening to them.

A little food for thought, FWIW.

 

[XS650]

quote:

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Originally posted by farang:
Saw lots of recommendation about HDEO (such as Delo 400, Delvac 1300) for high mileage gasoline engine for cleaning purpose!

I wonder is there anything that bad for the engine if used HDEO! Beside that, what else does HDEO do to a gasoline engine?

The cars in question are 91 and 95 Honda Accord! Both recommend 5w30 but most HDEO are 15w40. I am in LA.

Please advise!

---

There is a lot of experiance with HDEO in gas engines here, for instance I've used in it some gas engines since the late 1980s.

I don't recall anyone here having any problems traced to HDEO in gas engines. Just be sure it's also rated for gas engines, SJ or SM.

10W-30 is harder to find, but probably the best dino viscosity for your car. There is nothing wrong with 15W-40 in those cars except you will lose a bit of power and economy. You may or may not notice the difference. Probably not unless you really believe it will be worse

In hots parts of So Cal, your actual oil viscosity in cSt (that's what really counts) with 15W-40 won't be much differnt than what someone in Seattle gets with 10W-30.

I think the benefits of HDEO in gas engines are overstated a bit and the problems are non-existant. In the end it won't make a lot of difference one way or the other.

 

[Jelly]

Some benefits:

1. Extra detergents/dispersants to keep a gas engine clean and performing at "top-notch" for a very long time.

2. Extra additives that prevent top ring land fill and prevent ring sticking/breaking.

3. Extra protection at high-temps and high-loads.

4. In comparison to PCEO's, VII's in HDEO's are carefully selected to minimize shearing.

5. HDEO will lower consumption while having a minimal or un-noticeable effect on fuel economy, as well as offering capability of extended drain intervals.

The main reason I use HDEO's in gas engines is for incredible engine cleanliness...

[ January 18, 2005, 03:39 PM: Message edited by: Jelly ]

 

[Jimbo]

I have been using Delo 400 in several vehicles for many years. Extra detergent/dispersant is only one advantage. The extra ZDDP for boundary lubrication, particularly for older flat-tappet gasoline engines is also important. Since you are in LA, our warm climate makes 15W-40 an ideal weight for older engines. In a four-cylinder Mopar engine, oil usage was eliminated compared to 10W-30.

My UOA's with Delo show single digit wear metals, even with slightly extended drain intervals. The reason Amsoil and Redline diesel oils are different is because they are formulated with such a high TBN for ultra-extended drains in diesel engines to justify the high cost that the ash content may foul spark plugs. Delo, Delvac, Rotella, etc, still carry API gasoline engine ratings.