Rotella T6 in Flat Tappet Gasser: High Detergent and No Friction Mods

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Some people trust Shell Rotella T6 to protect gasoline engines with flat tappet camshafts, provided the viscosity is suitable. Although T6 has good zinc and phosphorus levels, these engines don't require its high detergent, which can reduce zinc/phosphorus effectiveness in gas engines. Additionally, T6 lacks friction modifiers (it's wet clutch compatible), which are desirable in this application.

In a gasoline engine with a flat tappet camshaft:
1. What are the implications of the lack of friction modifiers?
2. I've understood that Shell Rotella T6 has about 1100 ppm phosphorus and 1300 ppm zinc (equivalent to M1 TDT). What would be the implications of using S-rated oil with 100 ppm less phosphorus and 200 ppm less zinc?
3. Would T6's high detergent levels and lack of friction modifiers cause you concern?
 
What engine exactly do you have that has flat tappets?

And since you're asking about a gasoline engine not a diesel one, you should consider asking a moderator to move this thread. It's posted in the wrong forum.
 
O.P:

What engine, cam intended rpm and duration?

Of just bench racing?

You can buy zdp from cam manufacturers and add that to your sump of preferred low over-base oil

But I never had a GM cam go over 80-100K miles on high ZDP API service SE or SF oil, though.

And that was with seat pressures under 90lbs and lift under .450" with a 1.6 advantage rocker.
 
Originally Posted by viscous
Some people trust Shell Rotella T6 to protect gasoline engines with flat tappet camshafts, provided the viscosity is suitable. Although T6 has good zinc and phosphorus levels, these engines don't require its high detergent, which can reduce zinc/phosphorus effectiveness in gas engines. Additionally, T6 lacks friction modifiers (it's wet clutch compatible), which are desirable in this application.

In a gasoline engine with a flat tappet camshaft:
1. What are the implications of the lack of friction modifiers?
2. I've understood that Shell Rotella T6 has about 1100 ppm phosphorus and 1300 ppm zinc (equivalent to M1 TDT). What would be the implications of using S-rated oil with 100 ppm less phosphorus and 200 ppm less zinc?
3. Would T6's high detergent levels and lack of friction modifiers cause you concern?

1)Friction modifiers increase Miles per gallon.
2) Hard to say probably a minuscule difference
3) No and no.
 
Originally Posted by viscous
Some people trust Shell Rotella T6 to protect gasoline engines with flat tappet camshafts, provided the viscosity is suitable. Although T6 has good zinc and phosphorus levels, these engines don't require its high detergent, which can reduce zinc/phosphorus effectiveness in gas engines. Additionally, T6 lacks friction modifiers (it's wet clutch compatible), which are desirable in this application.

In a gasoline engine with a flat tappet camshaft:
1. What are the implications of the lack of friction modifiers?
2. I've understood that Shell Rotella T6 has about 1100 ppm phosphorus and 1300 ppm zinc (equivalent to M1 TDT). What would be the implications of using S-rated oil with 100 ppm less phosphorus and 200 ppm less zinc?
3. Would T6's high detergent levels and lack of friction modifiers cause you concern?

1)Friction modifiers increase Miles per gallon.
2) Hard to say probably a minuscule difference .
3) No and no.

Are you implying motor cycle engine.
 
Originally Posted by kschachn
What engine exactly do you have that has flat tappets?

.
whole bunch of Jeeps still running around with the 2.5 and 4.0 including me. Cam problems on these are rare but it does happen. The guy next door to my work lost a couple of lobes on his 02.

But I suspect that there may be other reasons why.
 
And most Japanese shim under bucket DOHC. Toyota and Nissan and Ford big fours from a few years ago.
But these 16V have VERY light valve springs, though the wear can be do to forces generated during rapid acceleration of the mechanism at high rotational velocities
 
Ive seen tons of these posts/questions over the years.. here is my 2 cents.

VR1 is $6.80/qt
T6 is $5.80/qt

Spend the $1
 
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