Engine Oils

[alolmo]

My 1970 GT engine has about 80,000 mls. it runs very well it is original. For the las six years I've been using Penzoil 10/40 high mile engine oil. Shoul I switch to a sintheric oil like Rotella T? what weight? What are you guys ussing in your originals engines?

[ungermm]

I'm using Rotella T 15-40W in my 1970 rebuilt engine. Rotella T isn't a synthetic. I decided to use it after reading this thread.

http://www.opelgt.com/forums/6a-engi...-problems.html

Jerry

[ghcoe]

I'm using Rotella T 15-40W in everything I own, atvs, boat, cars, lawn mower. Just hope they do not decide to cheapen out too.

[alolmo]

OK, Rotella 15-40w it is. I will continue to read up on the subject, the more I look into it the more I realize there is a lot to learn. The only thing about Rotella is that I don't know what the concentration of ZDDP is, and since I already use Comp Cams' oil additive I don't want to add to much of it.

[West Coast GT]

I use 30 weight oil in my Opel (original engine). Every so often I throw in some oil treatment like Slick 50 (or whatever it is). The temperatures around here don't get below freezing so I don't use those oils with a viscosity range.

In Sacramento, I'd be tempted to run something thicker in the summer.

[Redskinsjbs]

Well after reading the supplied thread, my impression is that Rotella-T has a changing formula which *may* now make it worse than it was before, Brad Penn is another choice, and the third option is to use a Zinc additive.

I have no idea what I should do. Can someone simply tell me? (ie, Jay, Put XXXXXX in your unknown-mileage '72 Opel engine)

[Viny Charb]

I've been using HD Diesel oils like 15w40. They have a tendency to have much higher zinc values then gasoline oils.If I had a higher performance engine I would probably use something different but for a stock unrebuilt 1.9 it works fine.

[Paul]

While the Rotella 15W-40 is great for our older Opel engines, DO Not use it in a Modern Gas engine designed for 5W-30 or 10W-30 oils

[2 Fast 4 U]

I changed from 10W40 to 20W40 this oil is specially made for older cars like ours, it's a little bit thicker than the 10W40, and doesn't has as many dopes as the modern oils have, our cars ran good on it back then, so why not use it today, and the nicest thing its allot cheaper than the 10W40

[opelwasp]

Other choices include AMSOIL and Redline. They both have high concentrations of ZDDP. I use Redline personally.

[alolmo]

Now I read some where that 1-sintheric oils are better, for a number of reasons: durability, lubrication, etc. And 2-that once one start using these oils it's best never to change (mix)

[RallyBob]

Originally Posted by opelwasp Other choices include AMSOIL and Redline. They both have high concentrations of ZDDP. I use Redline personally.

Surprisingly the Amsoil is pretty low on the ZDDP scale, I presume in order to appeal to users of late-model cars (high ZDDP levels will damage catalytic converters). But I used nothing but Amsoil on my WRX for 78,000 miles and it still ran like a top when I got rid of it...no oil burning at all. Good stuff, but not really suitable for flat-tappet (older) engines. However most 'racing' versions of synthetic oils have higher levels of ZDDP.

The Redline is great stuff I must admit. Just pricey. I used to use this exclusively on my Opels, but more recently I switched to Brad Penn oil as it's half the price.

[Redskinsjbs]

Bob,

What weight Brad Penn do you use?

[RallyBob]

Originally Posted by Redskinsjbs Bob, What weight Brad Penn do you use?

Depends on the engine, mileage, and application. I actually use it on my Nissan Pathfinder with 200k on it, but I mix 20W-50 and 10W-30 in a 50/50 ratio, basically leaving me with 15W-40. Running straight 'generic' 10W-30 oil it burned quite a lot (2 qts every 5000 mi.), with the Brad Penn mix I have now it uses 1/2 qt every 5000 miles.

For a new 'street' Opel engine, 10W-30 is fine. For a racing engine, high performance street engine, or higher mileage Opel engine, I use the 20W-50. The clearances on an older engine are huge compared to what modern cars run. If I lived where it was hot all year, I'd probably run 20W-50 as well, regardless of the engine mileage.

[gtkid2]

Mobile 1 is very good... my dad uses it in his opel.

[OriginalOpelGTOwner]

I read all I could about ZDDP. Turns out Valvoline developed a ZDDP engine oil for Roush Racing given Roush saw the need to fill a void for engine oil for classic car engines with flat tappet valve trains. The Roush oil is similar to Valvoline VR1 10W30. I wrote an email to Valvoline tech people and described my original Opel GT parameters and asked for their recommendation given they are familar with the ZDDP dialog on the internet and such. To my surprise, I received an email from them recommending Valvoline Premium Conventional motor oil. They stated in the email that Valvoline Premium Conventional oil has plenty of ZDDP and anti wear additives for my stock Opel engine. They have a proprietary ZDDP additive that does not deplete with mileage. Given all the above, I decided to use Valvoline Premium Conventional 10W30 engine oil about 3000 miles ago. I have 38,000 original miles on my engine.

[opellane]

Originally Posted by OriginalOpelGTOwner I read all I could about ZDDP. Turns out Valvoline developed a ZDDP engine oil for Roush Racing given Roush saw the need to fill a void for engine oil for classic car engines with flat tappet valve trains. The Roush oil is similar to Valvoline VR1 10W30. I wrote an email to Valvoline tech people and described my original Opel GT parameters and asked for their recommendation given they are familar with the ZDDP dialog on the internet and such. To my surprise, I received an email from them recommending Valvoline Premium Conventional motor oil. They stated in the email that Valvoline Premium Conventional oil has plenty of ZDDP and anti wear additives for my stock Opel engine. They have a proprietary ZDDP additive that does not deplete with mileage. Given all the above, I decided to use Valvoline Premium Conventional 10W30 engine oil about 3000 miles ago. I have 38,000 original miles on my engine.

I just purchase this Valvoline VR1 20W-50 Motor oil from Walmart.
After looking at every quart of oil for ZDDP Additive, this is what I am using in my Opel. It says it on the back of the bottle. It's the only oil I found that is printed on the back ZDDP additive provides tough anti-wear protection.
Not sure if all stores carry Valvoline VR1 Racing Oil. I'am also going to use this oil in my MGB.

[ghcoe]

From what I have read most oils still have ZDDP. It is just not in enough quantaty to satisfiy a old engines requirements. I would watch what they put on their label. Sure it may have ZDDP, but how much?

[SpringGT]

Originally Posted by opellane I just purchase this Valvoline VR1 20W-50 Motor oil from Walmart. After looking at every quart of oil for ZDDP Additive, this is what I am using in my Opel. It says it on the back of the bottle. It's the only oil I found that is printed on the back ZDDP additive provides tough anti-wear protection. Not sure if all stores carry Valvoline VR1 Racing Oil. I'am also going to use this oil in my MGB.

I have used Valvoline VR1 20W50 in my Porsche nearly since it was new (25 years and 145,000 miles). It still has good oil pressure and it makes no smoke.
Valvoline may have changed the ZDDP content during that time, I don't know, but I have had very good service from it. I have also used Slick50 in it periodically during most of that time. FWIW.
Bob

[hrcollinsjr]

Originally Posted by RallyBob ...not really suitable for flat-tappet (older) engines. However most 'racing' versions of synthetic oils have higher levels of ZDDP.

This applies to more than our Opel's. I suspect a few of you have older farm tractors and expensive lawn mowers. I bought a commercial lawn mower figuring if I took care of it that I wouldn't need another and was using Mobil 1in it. My uncle, a Scag dealer, has been trying to get his customers especially his commercial customers to switch from Mobil 1 because of the lack of ZDDP.

I tried Mobil 1 turbo diesel oil in my basically new McCormick turbo diesel tractor. I had to add oil between changes. I didn't need to with the conventional oil that came in it. I have decided what I'll change to but my brother in law used Mobil Delvac in his truck. I used Castrol Diesel oil in my old BMW. Haven't done any research on the previously mentioned oils but don't figure you can go too far wrong using name brand oils.

Harold

[alolmo]

The reason I started to think about all these issues regarding to engine oils, viscosities, and ZDDP contents, was because my oil pressure in dash is to the highest, and so I thought that maybe I try changing the oil and see if there was any difference;nothing change. I have some oil leaks, the typical suspects, but I don't seem to burn any oil. I wonder if my sending unit is kicking the bucket.

[ben]

i am valvoline man for life
but i put the full synthetic in opel
didn't like oil leak's
then found out that when i took the valvoline certification test's
that synthetic can case oil leak's on old car engine because of the type gasket even on a new rebuild
so valvoline doesn't recommend full synthetic old cars for that reason
so i went to max life oil which is a blend and that what i run in all my cars

[opelwasp]

Synthetics in old cars are fine. Synthetics put in an engine with old gaskets not good.

[trlmr]

A couple things to keep in mind, #1 Synthetics are not the best oils to prevent corrosion. If you don't drive your car much, corrosion is a big deal. #2 No single grade oil has the SM rating with the lower ZDDP requirements. This of course doesn't mean all single grades have high zddp levels. If you are into single grades, would look for a single grade with an older CF-4, CD or CDII rating in addition to the gasoline engine rating.

Edit: If I remember correctly, Single grades won't have the CF-4 rating, the highest they went was CF

[yellaopelgt]

My thoughts are that if an engine has been run on regular oil its entire life, it should keep the pace. If you add an additive such as slick 50, your gonna get oil leaks. Its a synthetic, and it will find its way out of the seals. They really just dont mix well together. One or the other. Keep it simple.Shell Rottella.
joe