Mobil 1 15w-50 full synthetic for flat tappet?

[cjshaker]

I'm thinking about switching to Mobil 1 15w-50 full synthetic in my 427 solid lifter engine. I've always shied away from full synthetics on flat tappet engines, but according to their data, this stuff has pretty good zinc content to work with flat tappet cams. I'm curious what the engine builders have to say, or if anyone has used this stuff in flat tappet engines with good success? All of their other racing oils are 0 or 5 weights, which is too thin for my liking.

[mbrunson427]

https://www.amsoil.com/shop/by-product/motor-oil/gasoline/z-rod-10w-30-synthetic-motor-oil/?code=ZRTQT-EA

The label says all the right things on this stuff. Expensive though.

[rcodecj]

I've used Mobil 1 15w-50 full synthetic for decades with no problems. Mobil 1 also makes a 0w40 full synthetic with zinc that I've used but before I used any of them I would check the Mobil 1 site as they do change formulas sometimes.

[Stangman]

I am using 10-40 Brad Penn and feel pretty comfortable with it. I have about 1500 miles on it and oil is still real clean. Now I do change it whenever I feel like it, or on a whim because I take it to the track but it always feels very slippery when it get on your hands. Ive felt many an oil and sometimes I wonder how motors last the oil feels like water and like just wisks away on your hands no slippery feeling. I do like the extra thickness and thats probably what you like also. Maybe you should ask about your clearances and go from there. I was advised to use 10-40 for the clearances that I have from builder.

[64PI]

I've been running Brad Penn 10w30 in my 451" flat tappet engine for 4 years now. Like Stangman  mentioned its very slippery stuff. I just tore down a 390 I had together for 10 years that has seen approx. 20,000 street miles and countless passes. That engine has been through Rotella, V-R1 and Brad Penn.. The bearings looked new and the 294s comp cams looks new. Bradd Penn gets my vote but I'm curious to hear what people have to say about mobil....

[cjshaker]

I suppose I should have mentioned that clearances range from .0025-.0035. The engine has probably 5k road miles and about 30 track passes, so it's broke in. With my clearances, zero or 5 weight is not something I want to go to. I've been using Rotella 15w-40, but I think they've dropped some of the zinc additives from their newest blends. As usual though, details are hard to come by. Mobil is pretty open about their blends and zinc content, at least on their website. My concern is for the flat tappet cam.

[Stangman]

I think my clearances were 0025-0028 so maybe thats why Im 10-40. I never inquired but does Brad Penn have a 20-50?
I am also using a solid Doug. With those clearances 20-50 dont sound unreasonable.

[CaptCobrajet]

 I like Valvoline VR1 SAE 30.  I wouldn't use the full synthetic oils until it has a lot of miles on the rings.  Like maybe 15000.  Just my opinion.  It needs to be sealed and "worn in" for a while on regular oil.  If not, it will always consume a little.  In '09, my brother and I both got new 4.6 Mustangs for our wives.  He went synthetic from day one.  I brought ours home and dropped the oil out, and put dinasour guts in mine.  I ran it 20K on conventional VR1, then switched to synthetic.  Both cars have a little over 100K now.  His uses some between changes.  Mine does not.......

Just a side note......cars with cats won't like the zinc oils long-term.  It plugs them up.

[Stangman]

I dont think Brad Penn is synthetic, I will have to look maybe its synthetic blend? I was thinking when I bought it that I didnt want synthetic cause evryone says synthetics have more oil leaks. I dont know if thats a thing with FEs cause they leak anyway alot of times. But I know I ran my brake in 30 weight BP for like 50 miles then changed the oil and filterwith new break in oil for 500 miles then went to the 10-40. Maybe its overkill but I thought I was  protecting my investment.

[cjshaker]

Blair, thanks for the input. I wondered if that was enough miles. I think I will go with the VR1, which I already have several cases of.

I also have an '09 GT, bought in early '10 with only 3k miles. I've always used full synthetic, but it only has 28k on it currently. Don't drive it much.

[Katz427]

I know this topic has been discussed many times. My experience has been altered in that at work or customers were having pump failures we had never seen before with the diesels. Checking the oil for additive package , we found that the zinc had been reduced, but should not have caused the failures we were seeing.
The parts were sent to metallurgist and he discovered that one of the other extreme pressure additives had a greater affinity for plating the metal surface, than the zinc. The zinc basically did nothing. This info was passed along to our oil supplier.
What does it mean? IMO forget focus on zinc and go with what has worked. Depending on the additive package the zinc content may be misleading.

[ACHiPo]

I suppose I should have mentioned that clearances range from .0025-.0035. The engine has probably 5k road miles and about 30 track passes, so it's broke in. With my clearances, zero or 5 weight is not something I want to go to. I've been using Rotella 15w-40, but I think they've dropped some of the zinc additives from their newest blends. As usual though, details are hard to come by. Mobil is pretty open about their blends and zinc content, at least on their website. My concern is for the flat tappet cam.

Doug,
I emailed both Shell and Chevron to ask about ZDDP levels in their diesel oil (Rotella and Delo) as I was figuring out what to run in my new 470 FE with flat hydraulic tappets.  Chevron reduced their ZDDP from ~1200 to 800 ppm and added other additives (ash?) to compensate while meeting EPA standards.  Shell Rotella still has 1200 ppm ZDDP.  I have no idea why Shell is able to make their higher zinc additive compliant while Chevron (and other companies) couldn't.

A member of our Cobra club was a development engineer for Chevron in charge of their racing program for many years.  He convinced me that the 1200 ppm ZDDP diesel oil is the best for performance engines (claims even race teams sponsored by Penzoil, etc. used Chevron Delo because it flat worked in race conditions).  He recommended using Delo, but adding ZDDP additive since the Delo now has reduced zinc.  I understand his loyalty to Chevron, but that seems a little silly when I can get Rotella that already has the right zinc level in it.  I'm planning to use the Rotella starting my first oil change.  Given the relatively low mileage my Cobra will see, I figure dino makes more sense since I'm going to want to change the oil every 3k anyway.

I'll close by saying that the whole oil thing is a mystery, in large part because of the proprietary nature of the compounds.  There's a whole lot of opinions, but the only folks that really seem to have data are the oil companies, and they wrap marketing-speak around everything.

[Katz427]

The reason Shell has kept zinc levels relatively high is that Rotella oil is listed strictly for diesel use.  It is not to be used in new cars with converters as Blair stated, the zinc causes degradation, and pollutes the catalyst  media in the convertor and that leads to shortened life.
So far, I have not heard of those zinc levels causing problems with DPF filters.

[plovett]

Yes.  You can use it.  I have been using it for as long a I can remember with my solid flat tappet.  I have about 405 lbs open pressure, nitrided cam and EDM lifters.   I like synthetic because I have a half-filled block so I know the oil temps are higher.  Also, you get maybe a 1% gain in power.  Not a lot but something.

I usually get it at Wal-Mart for about $23 per 5 quarts?

JMO,

paulie

[wayne]

VR1 all the way for me its all i use no trouble ever,