How bad is lugging ?

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106
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Minnesota
The 3 cylinder Geo Metro (Suzuki motor)was said to have an issue from owners lugging the motor to increase the miles per gallon, can't remember what, but seems someone told me to let it wind out was the best for it. I had a 1991 Metro, 5 speed manual.
 
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3,026
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Western S.C.
"Lugging" is subjective and, unless taken to ridiculous extreme, is generally overrated as a hazard to engines. By some people's understanding, I lugged all my manual-transmission cars, and none of them ever showed any hint of bearing trouble.
 
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"Lugging" is subjective and, unless taken to ridiculous extreme, is generally overrated as a hazard to engines. By some people's understanding, I lugged all my manual-transmission cars, and none of them ever showed any hint of bearing trouble.

Good point. There is a big difference between lugging a engine on a flat street versus lugging going up a hill.
 
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721
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New Hampshire USA
If this continues buy an automatic{ joking}. I once tore down a truck engine that showed more wear om the top bearing than the bottom. Plastiguaged to .003 this at 200,000 mi. Lugging?
 

M119

Thread starter
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227
Location
Brittany, France
If this continues buy an automatic{ joking}. I once tore down a truck engine that showed more wear om the top bearing than the bottom. Plastiguaged to .003 this at 200,000 mi. Lugging?
I would rather have an automatic but they are hard to come by here. The only two AT cars i owned were an W210 E class and a Pontiac Trans Sport 3.8 V6.
 
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12,939
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ROCHESTER, NY
Too many responses to read through so I though I'd through in my opinion based on how I understand lugging in today's engines. And this may have been mentioned already.

Also, I don't know how this effects the engine with manual transmissions due to the driver having control.

I don't know how advanced the engine are in the OP Merc's, and it may have been mentioned. But here's how I understand lugging in new engines.

Today's engine are designed to be lugged due to the way new modern transmissions are designed to keep the engine(s) in the lowest RPM possible for all situations.

Especially with gears beyond 6 speeds. These new "alternative" automatic transmissions such as 7 & 8 speed DCT/DSG, CVT & 8, 9 & 10 speed conventional autos.
 
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375
Too many responses to read through so I though I'd through in my opinion based on how I understand lugging in today's engines. And this may have been mentioned already.

Also, I don't know how this effects the engine with manual transmissions due to the driver having control.

I don't know how advanced the engine are in the OP Merc's, and it may have been mentioned. But here's how I understand lugging in new engines.

Today's engine are designed to be lugged due to the way new modern transmissions are designed to keep the engine(s) in the lowest RPM possible for all situations.

Especially with gears beyond 6 speeds. These new "alternative" automatic transmissions such as 7 & 8 speed DCT/DSG, CVT & 8, 9 & 10 speed conventional autos.
Pretty much. I've even read in some owners' manuals that say "you may hear a light knocking noise when the car is travelling uphill, this is within normal operating conditions and is meant to maximize fuel efficiency".

All in the pursuit of the EPA.

I drive manual and I only lug my car in second gear when I've slowed down so much that 1st gear has locked out, and 2nd doesn't generate much punch. Usually only happens between 10-16 kph.

But I always make sure to never floor it in these cases and gently bring the vehicle back up to speed.

Otherwise I prefer higher revs. Keep the engine between 2.2-3.3k.

This is on a new WRX.
 
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Pretty much. I've even read in some owners' manuals that say "you may hear a light knocking noise when the car is travelling uphill, this is within normal operating conditions and is meant to maximize fuel efficiency".

All in the pursuit of the EPA.

I drive manual and I only lug my car in second gear when I've slowed down so much that 1st gear has locked out, and 2nd doesn't generate much punch. Usually only happens between 10-16 kph.

But I always make sure to never floor it in these cases and gently bring the vehicle back up to speed.

Otherwise I prefer higher revs. Keep the engine between 2.2-3.3k.

This is on a new WRX.


If your engine is lugging in second gear at those speeds then that is what we used to call a gutless vehicle.

Is it really lugging? Maybe the meaning has changed over the years.
 
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15,267
Location
N.H, U.S.A.
With a performance-tuned engine sporting long duration cams and a low velocity intake, you would say it was "off the cam" down bottom; You could even get a backfire if you opened the throttle too much down low. But like I mentioned here earlier before, an Otto-Cycle engine (your 4-stroke) at 1200 rpm is firing each cylinder 10x per second**, multiply that by 4 cylinders = 40 power pulses per second ! Back in the 1930's with big bore, long stroke, very low compression engines, that would be in the middle of the power band!

** example: 1200 rpm / 60 sec per minute = 20 revolutions / second. Then divide that by 2 (as in a 4-stroke you only get a power pulse every other time around) = 10 power pulses per second per cylinder.

So on a V8 engine with 8 cylinders you get eighty power pulses per second.

Lug that! General duty V8's should be tuned to make good torque++ from 900 - 3200 rpm. like the old days.

++ approximately 1.2 lb-ft per cubic inch displacement. So a 350 V8 should make 420 lb-ft at say 2600 rpm.
 
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375
If your engine is lugging in second gear at those speeds then that is what we used to call a gutless vehicle.

Is it really lugging? Maybe the meaning has changed over the years.
Nope it lugs in second if you're not slipping the clutch.

https://www.reddit.com/r/WRX/comments/77uacx
https://www.reddit.com/r/WRX/comments/buyvm1
It's only a 2.0L engine. The turbo is what gives it its power. Boost comes in around 2.4K.

It's also the gearing of these gearboxes. 2nd takes you to 60mph, it's basically half of 1st gear.

I'd much rather have a shorter second gear and need to hit third to go to 60mph. 0-60 is such a stupid measure and this is what we get when manufacturers chase it.
 
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I don’t slip clutches. Obviously your driving habits are much different than mine.

Good Luck.
 
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241
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MD
I don't stress downshifting to a lesser gear and sometimes shift to neutral and momentum would carry the car for short distances
 
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24,819
Location
PNW
With a performance-tuned engine sporting long duration cams and a low velocity intake, you would say it was "off the cam" down bottom; You could even get a backfire if you opened the throttle too much down low. But like I mentioned here earlier before, an Otto-Cycle engine (your 4-stroke) at 1200 rpm is firing each cylinder 10x per second**, multiply that by 4 cylinders = 40 power pulses per second ! Back in the 1930's with big bore, long stroke, very low compression engines, that would be in the middle of the power band!

** example: 1200 rpm / 60 sec per minute = 20 revolutions / second. Then divide that by 2 (as in a 4-stroke you only get a power pulse every other time around) = 10 power pulses per second per cylinder.

So on a V8 engine with 8 cylinders you get eighty power pulses per second.

Lug that! General duty V8's should be tuned to make good torque++ from 900 - 3200 rpm. like the old days.

++ approximately 1.2 lb-ft per cubic inch displacement. So a 350 V8 should make 420 lb-ft at say 2600 rpm.
Would you say operating a single cylinder engine at 900 RPM at WOT is "lugging"? If so, the same thing is happening to every cylinder regardless of how many cylinders there are.
 
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297
Location
EU
With the stereotypical Lanz Bulldog 900rpm might be regarded as over-revving. It ain't the same thing regardless of how many cylinders overlap their work cycles and else.
Some highlighted aspects in here are dependent on the drivetrain not being perfectly stiff or the PTO not running from a massive flywheel. Rotational variancies as part of the explanations otherwise wouldn't matter. Adding a cylinder or two quite obviously affects the minimum flywheel size or the minimum rpm.
 
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297
Location
EU
Yeah, the 56 cylinder Zvezda should have been the good lugging answer. Unfortunately they only ever had enough luggage for the 42 cylinder in a tractor.
 

M119

Thread starter
Messages
227
Location
Brittany, France
Back to my experiment with 5w30, i feel like the engine is a tiny bit more responsive than with a 40 but i can't believe a few less cSt can make a difference, is it possible or just a placebo? Or maybe the oil just stays cool enough in this big sump/small displacement engine to have a wider difference between a 30 and a 40...
 
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