Lugging even with computer control?

[LoneRanger]

Lugging puts a lot of load on the main crankshaft bearings at a time when hydro-dynamic wedge is nearing marginality. Hope you guys lugging at sub 1200 rpms are using an oil with an HTHS > 3.0

 

[SilverFusion2010]

Originally Posted By: LoneRanger
Lugging puts a lot of load on the main crankshaft bearings at a time when hydro-dynamic wedge is nearing marginality. Hope you guys lugging at sub 1200 rpms are using an oil with an HTHS > 3.0





The ecoboost are all 5w30 now so 3.1-3.5 depending on if they grab an ilsac or not

 

[Olas]

Manuals only ever 'lug' when you MAKE them do it.

 

[CR94]

Originally Posted By: LoneRanger
Lugging puts a lot of load on the main crankshaft bearings at a time when hydro-dynamic wedge is nearing marginality. Hope you guys lugging at sub 1200 rpms are using an oil with an HTHS > 3.0
The people who program automatics know how to calculate whether bearing lubrication is fully hydrodynamic, assuming the recommended oil is in use. If not extreme, "lugging" is good. Worrying about it in most cases is much ado about nothing.

When power demand is sufficiently low, my Prius likes to "lug" at ~1100RPM. I habitually did the same manually in my Mazda and it scored over 600k miles with zero bearing issues.

 

[meep]

well, and true lugging...and you know it. it rattles hard and you feel the engine failing below the point where it's providing any useful power. I don't feel ours is lugging at the speeds/output its commanded to perform-- I just feel the vibration. I'm not sure that really qualifies as "lugging." Engine dynamics probably play a role too - 900 RPM in 4th gear in a recent focus RS was not uncomfortable at all - impressive actually. 900 RPM in my 86 escort was lugging as it couldn't move and just made a lot of fuss. It's not just the rpm. Probably diversity of timing map, valve programming and considerations like stroke...?

-m