[Andy5150]

I have been running rotella in my 360 for about 7000 mi, because of the added protection for flat tappet cams. Yesterday, I was watching a Speed channel hot rod show, and when talking about oils, they said that while rotella was a good break-in oil, it would cause sludge build-up if used long term. Is this true,and if it is what would be a good oil to use in a carburated amc 360? Thank You.

[OldSailor]

I've been using Royal Purple 10W-30 in my AMC 360 for about 10 years of so. No problems with it. However, I change it every 1000 to 2000 miles because my CJ7 is basically an offroad machine.

[x550x]

Originally Posted by Andy5150

I have been running rotella in my 360 for about 7000 mi, because of the added protection for flat tappet cams. Yesterday, I was watching a Speed channel hot rod show, and when talking about oils, they said that while rotella was a good break-in oil, it would cause sludge build-up if used long term. Is this true,and if it is what would be a good oil to use in a carburated amc 360? Thank You.

I'd want to see some actual data confirming this before I believed it. Did they say why it causes sludge?

[gmakra]

You will hear a lot of feed back on preferences on oils. Some will say regular oil and some will say synthetic. Currently I am running 10-40 with an additive called ZDDP Plus ( http://www.zddplus.com/ )

I figure just putting back the ZDDP in the oil is the simplest thing to do to make the oil similar to oils of the past. The EPA is also making the oil manufactures lower the ZDDP in the Diesel oils. And while some people swear by Rotella the diesel engine is a completely different animal so the additives are different. I was waiting for some long term usage results before I considered changing.

[scottymac62]

Originally Posted by x550x

I'd want to see some actual data confirming this before I believed it. Did they say why it causes sludge?

The sludge that you are talking about is caused the high detergent content in the Rotella oil. The sludge is the old oil that is being cleaned up that has been stuck in your engine for a long time. That is why it is suggested that you change your oil filter every 1000 miles for the first 4 or 5 thousand miles when you first start using Rotella. I switched to Rotella about 7 thousand miles ago and I'm pleased with the results.

http://www-static.shell.com/static/ca-en/downloads/shell_for_businesses/oils_lubricants/rotella/rotella_fact_sheet.pdf

[x550x]

Originally Posted by scottymac62

The sludge that you are talking about is caused the high detergent content in the Rotella oil. The sludge is the old oil that is being cleaned up that has been stuck in your engine for a long time. That is why it is suggested that you change your oil filter every 1000 miles for the first 4 or 5 thousand miles when you first start using Rotella. I switched to Rotella about 7 thousand miles ago and I'm pleased with the results.

http://www-static.shell.com/static/ca-en/downloads/shell_for_businesses/oils_lubricants/rotella/rotella_fact_sheet.pdf

That sounds reasonable, but "break in" would indicate that the engine was new, thus no gunk to begin with. Are they saying that the oil would cause gunk if Rotella was used from the very beginning?

[stilesg57]

for what it's worth...used Rotella in my diesel Suburban for 13 years and 215,000 miles. No problems, no complaints.

[dwloop]

One more thought, although I love to watch the car shows on Speed and Spike TV on Saturday and Sunday mornings, do you believe everything that is presented there? I mean, they advertise Z-Max as well...

I had thought that Shell reduced the amount of zinc and phosphorous in Rotella like many other oils recently. Those are the components needed for flat tappet cams to survive long term. I still use a ZDDP additive unless the manufacturer specifically states they have it, like Royal Purple or Joe Gibbs oils.

Dave

[redhawk4]

It would be interesting to see some hard facts. Sludge seems to only be a relatively recent problem, with a number of modern motors being particularly susceptable. I forget the reasons I've seen stated but one of them was the additional heat and the fact of running a much leaner mixture. I just don't remember hearing about sludge prior to the mid 80's. So it would depend on the type of motors they are talking about with regards to sludge build up if Rotella is used beyond a break in period. I believe sludge is a problem for lean burn gas motors not diesel so Rotella may not have the additives used to fight sludge in other oils.

I think if you change your oil regularly then sludge is not an issue. I also struggle to believe that a modern oils, which have added so much to vehicle longevity from when I first started driving, even with the deletion or depletion of additives would give poorer performance than the oils from the 70's regardless of flat lifters, but then what do I know, and as I've said before, we have no way to test this as individuals.

[Cutlass327]

Most vehicles nowadays have roller lifters instead of flat ones. These are designed more durability because of this, so they don't need the extra wear inhibitors.

[SuB8HaVeN]

Sounds like BS to me. What do you think tractor trailers run in their motors, and they go half a million miles?

[gmakra]

Cutlass your pretty close on that last comment. Actually the EPA mandated that a Catalytic Converter last longer than a 100K Miles. And they found that zinc was masking the converters thus decreasing efficiency and zinc being a scrafical metal for the camshaft forced the car manufactures to switch to rollers. So it wasnt about durability it was about warranties.

[Performance]

Rotella is one of the best oils out there. It does not create a sludge buildup. I have switched all my vehicles to Rotella including the Honda Civic. I have also been breaking all my new engines in with Rotella and a Comp cam additive if using a flat tappet cam. After break-in, it's straight Rotella. After 3500 miles in between oil changes, this oil still looks very good. The zinc and phosphorous count has been lowered in the Rotella too like all others, but it still has an extremely higher count than other conventional oils and the same amount as some of the racing oils. Other good oils to use is Valvoline VR1 race oil or any oil that has a label that states "For Offroad Use Only". Rotella has the same count of ZDDP and it's much cheaper than the race oils. I will say my street/strip engines have held up great with the VR1 oil. Now I will see how the Rotella does, long term, with a little more testing. So far no complaints.

[JeepHammer]

I think many are missing the point here...

Shell Rotella and Valvoline 15W40 are INDUSTRIAL GRADE OILS.
They have to live up to high standards of cleaning, particle suspension, detergents, thermal shock, friction breakdown, ect. than 'Consumer' grade oils do.

It's just 'Built' better than the light weight oils, keeps the engine cleaner, and it simply is TOUGHER than 'Consumer' oil is.

[x550x]

An article I came across recently.

http://www.highperformancepontiac.com/tech/hppp_0802_pontiac_performance_engine_oil/comp_cams.html

The '07 model year brought on many changes for diesel engines. Among them was an exhaust system catalyst, and another oil classification standard-CJ-4. One would assume from past events that the addition of said exhaust catalyst would ultimately lead to ZDDP reduction, but Shell's OEM Technical Service Manager, Stede Granger, says otherwise.

The exhaust catalyst found on diesel engines isn't the same as that of a typical passenger-car application, so we're able to retain high ZDDP levels. The API specification change to CJ-4 for 2007 has resulted in moderate zinc reduction from about 1,400 ppm to 1,200 ppm. And even at these slightly decreased levels, ROTELLA T 15W-40 conventional and 5W-40 synthetic still contain three to five times the amount of the desirable anti-wear additives as some current gasoline-engine oils.

1200 ppm is still a very high level of zinc. Looks like Rotella still has the higher zddp levels that our flat tappet engines like.