I used to think that, but then I started understanding windage and leakage. I now like 40 weight or even 50 weight
Hey, we haven't had a good oil war in a while...
- Thread starter Christo
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I used to think that, but then I started understanding windage and leakage. I now like 40 weight or even 50 weight
theres a LOT of conflicting statements in that article.
I'm liking this guy of late. He does some good testing.
www.youtube.com
This seems interesting
petrocanadalubricants.com
I'm liking this guy of late. He does some good testing.
The Motor Oil Geek
As a Certified Lubrication Specialist with over 20 years experience, The Motor Oil Geek channel delivers real data about motor oils from an expert perspective instead of speculation. Twice each month I will upload a new video that either analyzes a new oil, dyno tests an oil, reveals the details...
www.youtube.com
This seems interesting
Petro Canada | Digital Handbook | Automotive
petrocanadalubricants.com
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I decided to go with 10w40 Mineral Classic Oil High Zinc / ZDDP in the end from Westway Oils. I'm not in the US so struggle to get a lot of the brands mentioned here - I would have used the AMSoil but just couldn't find it available here in the UK/Europe.
For any non US GMC'ers this is worth adding to your consideration list;
www.westwayoils.co.uk
For any non US GMC'ers this is worth adding to your consideration list;
10w40 Mineral Classic Oil High Zinc / ZDDP
High Zinc SAE 10w40 Engine Oil A Low Detergent 10w40 mineral based engine oil specifically designed for use in Car and Motorcycles best suited to a period mineral oil and not todays high performance synthetic oils. The high zinc and phosphorus content provides extra wear protection needed at the...
www.westwayoils.co.uk
We've had our coach for about 12 years now, with the 403. Back when we first got the coach at 63,000 miles, I jumped on the forum to see what everybody said about what engine oil to use and did some extensive research. I finally decided on Amsoil Z-Rod 10W-30 and have put on about 10,000 miles on it, with about 3 changes during that timeframe. I chose this oil because it's specifically formulated for engines around this era and sticks close to the OEM 10W-30 spec from GM. For the first 2000-3000 miles it would consume about a quart every 500 miles or so. Over time, I noticed it seemed to consume less and less, and now it consumes basically none. I check it every time I depart and the level stays the same now. We have made other changes to the engine since, but I've had Amsoil do this same thing even with small 8 HP engines, one that would comsume oil extensively and Amsoil (10W-30 small engine oil) totally eliminated it. Coincidence? I'm not sure, but I'm sold on Amsoil and have had excellent luck in every application I've used it. It's not cheap by any means, but for the GMC it's well worth putting in premium oil especially with putting on low miles in my opinion. For what it's worth.
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Thats useful feedback thanks. I saw similar oil usage on my previous engine, a good quart every other fuel fill up. I was using Valvoline VR1 20w-50 as I seemed to have lower oil pressure and thought it might help.
I noticed since the rebuild I'm not losing that quart every 500 miles and oil pressure is much better. I'm also putting a digital gauge in for more accurate measurement as the dash gauge is not that sensitive.
Might convert over to the Amsoil after the next trip given its positive mentions on the forum here, and its claimed purpose does seem to match our use case perfectly.
I use nothing but 15/50 Mobil-1...Mobil actually lists the ZDDP content on their site....another point...if you are not running 300 lb+ valve spring pressures and not going more than 3000 miles between oil changes...600 is all yo need....before the high performance big blocks and 6000 rpm+ engines came into play no engine oil other than break and racing oil had big ZDDP numbers....Chrysler didn't use a spring strong enough in the Hemi to allow it to rev where it made real power (above 6000) so they didn't kill the cams..the hi-po 440 with hydraulic lifters was rated a higher rpm due to smaller and lighter valves...
YouTube channel Lake Speed's son (The Oil Geek) does a great job educating you about oil.....
People don't want to hear that...if more is better...TOO much is perfect...
ALL engine oil has ZDDP.....it/s how much balanced with other additives that are important....I just use 15-50 Mobile-1....AND I installed a dual parallel PH-8a size filter remotely behind the passenger wheel well....2 quarts....lowers pressure drop...lasts 10,000 miles..Before I bought my first GMC I had exactly zero automotive experience, I'd never changed oil or a spark plug. I've been playing catch-up ball. Not infrequently I would follow the opinion of a more experienced GMCer, one of the gurus.
Is the gotta-use-ZDDP-in-a-flat-tappet-engine dogma real world science or community general consensus?
Blackstone Labs is the household name in oil testing. Here's their article about running an engine without ZDDP.
ZDDWhat? | Blackstone Laboratories
How important is ZDDP in flat-tappet engines? Blackstone does an experiment to find out.www.blackstone-labs.com
An extremely small sample size, but he's Blackstone's lab manager, mechanical engineer, pilot, etc.,
Ryan Stark | Blackstone Laboratories
Ryan started at Blackstone in 1997 after graduating from Purdue University with a degree in mechanical engineering. Ryan is responsible for writing and maintaining Blackstone's software program, setting up and managing the lab, writing reports, and a million other things that need to be done in...www.blackstone-labs.com
The article is posted on Blackstone's web site, so it's pretty much their stance on the matter.
Is the ZDDP tide changing?
On the shelf at Walmart that have a good selection of Valvoline VR1. Specifically calls out flat tappet camshafts. The price was less than the Mobil 1 I bought for my roller cam engine. I would probably go with the VR1 oil in a flat tappet engine.
From the Valvoline website:
From drag strips to paved and dirt ovals, racing performance demands race-level protection. Which is why motorsport teams and enthusiasts depend on Valvoline VR1 Racing Motor Oil, America’s #1 racing oil. Our exclusive high zinc and phosphorus formulamotor oil is engineered specifically for modern and classic high-performance engines both on and off the track, which includes flat-tappet and performance cam motors. It’s chemically designed to reduce internal friction and enhance power output, while protecting critical engine parts from wear under the extreme conditions of racing. While its high load carrying characteristics, minimum foaming under stress and maximum resistance to thermal degradation ensure stability and lubrication. Valvoline VR1 Racing Motor Oil is recommended for high-performance gasoline engines as well as those burning full or partial alcohol fuels. It is not recommended for vehicles with catalytic converters or in wet clutches. Go with the proven winner, Valvoline's VR1 Racing Oil.
From the Valvoline website:
From drag strips to paved and dirt ovals, racing performance demands race-level protection. Which is why motorsport teams and enthusiasts depend on Valvoline VR1 Racing Motor Oil, America’s #1 racing oil. Our exclusive high zinc and phosphorus formulamotor oil is engineered specifically for modern and classic high-performance engines both on and off the track, which includes flat-tappet and performance cam motors. It’s chemically designed to reduce internal friction and enhance power output, while protecting critical engine parts from wear under the extreme conditions of racing. While its high load carrying characteristics, minimum foaming under stress and maximum resistance to thermal degradation ensure stability and lubrication. Valvoline VR1 Racing Motor Oil is recommended for high-performance gasoline engines as well as those burning full or partial alcohol fuels. It is not recommended for vehicles with catalytic converters or in wet clutches. Go with the proven winner, Valvoline's VR1 Racing Oil.
Motor Oil Geek's motto is "application dictates chemistry", so not sure that any racing oil is ideal for our application. That said, he talks about the revised formulation of VR1 here:
My last half dozen or so oil changes, I have switched from VR-1 to Mobil-1. The mobil-1 is actually less expensive and has better consistency in the oil pressure. I still have the factory oil pressure gauge, so the fluctuations I used to see with the Valvoline might not have been really happening, but the Mobil-1 still seems to be more even. I'm happy to see that an "expert" agrees with my choice of oil brands and weights.
Expert didn't need to be in quotes, his stuff is right up there with Bob is the oil guy.
I'm strictly a Bertolli EVO guy. I heard they put it in Maseratis, Ferraris and Lamborghinis...or maybe it was their drivers. Good stuff!
I use Valvoline VR1 its formulate for racing and classic engines. It seems to work well for me. Now I have an original low mileage engine, and have only put on about 4k, but all good so far.
I've been trying mobile one classic with zinc. It's made intentionally for vintage flat lifter engines. So far, so good.But I have not done in oil analysis. I may do so after the next week change.
I've started using VR1 personally. It's available widely, not terribly expensive and I like what I'm reading here.
Watch the weight of the oil. The 20W-50 takes longer to get to where it needs to go on start up and the higher 50 is outside our factory recommended oil weight. Hopefully it will flow through small oil galleries when hot. All the other stuff is absolutely great, but if the oil doesn't get to where it needs to go when it needs to get there, those areas will overheat and wear.
