• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

Motor Oil

Share this page

I don't know about white crows or black crows or magic juice, but what I do know is that the oil companies were putting in ZDDP in their oils for years until it was found to be detrimental to catalytic converters and O2 sensors. The oil companies didn't put that stuff in there just because they thought it would be nice for marketing purposes. It served a purpose. Once the ZDDP levels were dropped, it just seemed like there was a rash of cam and lifter failures. Coincidence??? Maybe. I don't know, nor do I care.

However, you can debate this back and forth all you want, but I'll err on the side of caution and make sure that the oil I put in my TR3 has sufficient amounts of ZDDP in it. Maybe it will save my cam and lifters. I don't see how it can hurt.
 
martx-5 said:
I don't know about white crows or black crows or magic juice, but what I do know is that the oil companies were putting in ZDDP in their oils for years until it was found to be detrimental to catalytic converters and O2 sensors. The oil companies didn't put that stuff in there just because they thought it would be nice for marketing purposes. It served a purpose. Once the ZDDP levels were dropped, it just seemed like there was a rash of cam and lifter failures. Coincidence??? Maybe. I don't know, nor do I care.

However, you can debate this back and forth all you want, but I'll err on the side of caution and make sure that the oil I put in my TR3 has sufficient amounts of ZDDP in it. Maybe it will save my cam and lifters. I don't see how it can hurt.
Click to expand...

And because it is your car and you pay the bills, right?

I also remember the rash of cam failures in this forum a few years back, mine included. I am of the opinion that we each need to do our own research and decide what oil to use. Notice I did not tell what oil I use because it is only my opinion, and only as valuable as everyone else's.
 
Randall... I agree that one can't test things under every possible condition, that would indeed be impossible. However, experiments could be constructed that would test the affects of varying amounts of ZDDP in typical, controlled and repeatable conditions. I for one would be very interested in seeing those results. I've spent a significant part of my career working around Tribologists (scientists that basically study wear between interacting materials) and those guys do that type of experimentation all the time... its just too bad it isn't with motor oils in old British cars... :smile:
 
One wonders why, since it's such a big issue, such tests haven't already been done... :confuse:

If there's a definitive voice on this, I sure haven't seen it!
 
Well, for one there is a lot of political pressure to get rid of older cars because they pollute too much. New car manufacturers are not going to fund it because they want everyone to buy new cars. Oil companies make more money from new cars and the newer formulations needed for advancing technologies. As big as the old car market is, its not big enough to fund extensive studies. Its far easier to put some ZDDP back into some, call it an oil for "classic cars" and charge an extra $2/quart.

Someone earlier mentioned the spring pressure aspect. In the hot rodding world where the cam/lifter failures first cropped up with the ZDDP reduction it was with the real high lift/high spring pressure combinations. My TR6 suffered lifter failure as well in 2001 on a newly rebuilt engine with a GP3 camshaft. Whether it was the reduced ZDDP or poor quality lifters is still undetermined. But agreeing with another earlier comment, I'm paying the bills so I will use what I want to use and what I have determined to work.
 
ZDDP levels were not reduced in gasoline motor oils until 2005 I believe, and diesel motors oil just last year. If and engine built in 2001 had lifter/cam problems it wasn't related to low ZDDP levels.
 
And cam/lifter problems have been VERY common since at least 1980 or so. Lots of finger pointing between engine builders, cam grinders and manufacturers ... seems like now they have found another direction to point the finger.

Lots and lots of tests have been run, although most of them have not been published on the 'net. Here's one interesting paper I found:
https://www.ciba.com/pf/docMDMS.asp?targetlibrary=_SalesAndMarketing&docnumber=29309
 
I have been running Shell Rotella T Multigrade Oil SAE 15W-40 in my Opel-GT. The engine is a modified, high compression, big valve, agressive cam and solid lifters. I rev it to 7K all the time with no lube problems.
*I have it in my TR3 now.
I also add 1/2 can of STP at every oil change.
Plus it's available at Walmart.
Lyle

<span style="text-decoration: underline">I wrote to Shell and asked about Rotella</span>.

"Lyle,
Shell Rotella T Multigrade Oil SAE 15W-40 contains approximately 1200 ppm zinc. That's about the same amount as API SJ-rated oils
contained prior to 2001, and about 50% more than found in most automotive gasoline engine oils in the market today. Historically, 1200 ppm zinc has performed well in protection of engines with flat
tappet camshafts.
Thank you for your interest in Shell Lubricants!
Regards,
Edward A. Calcote
Staff Chemist
Shell Lubricants US Technical Information Center
https://www.shell.com/us/lubricants"
 
Mark Jones said:
ZDDP levels were not reduced in gasoline motor oils until 2005 I believe, and diesel motors oil just last year. If and engine built in 2001 had lifter/cam problems it wasn't related to low ZDDP levels.
Click to expand...


The reduction in ZDDP actually began in the mid 80's with the implementation of OBD-I systems. The general public was only largely made aware of it with the latest SM classification of gasoline motor oil at the end of 2004. It began with SF rated oils and SG, SH, SJ and SL all saw further reductions.

The higher the spring pressure, the more the ZDDP is needed. But even stock engine camshaft profiles can generate 200,000psi between the tappet and the camshaft.
 
I did a MGB lifter rockwell test and posted the results on the MG section. Its down at the end of page 4 or top of page 5 today. It may be a interesting read for TR people interested in cam and lifter issues. Bob
 
Back
Top