Max RPM question - Jeep Garage - Jeep Forum

Go Back   Jeep Garage - Jeep Forum > Jeep Platform Discussion > Grand Cherokee - WK2 - > 2014+ Jeep Grand Cherokee Ecodiesel 3.0

Join Jeep Garage Today
Reply
 
Thread Tools Display Modes
 
  #1  
Old 02-22-2016, 10:50 AM
Member
My Jeep: 2014 3.0L
 
Join Date: Sep 2015
Posts: 23
Thanks: 0
Thanked 3 Times in 3 Posts
Rep Power: 462
biggiefl is on a distinguished road
Max RPM question

I have a 2014 I have owned for about 14 months and 14k miles(not a single problem nay sayers). Usually drive in eco mode and am happy with MPG and performance. Have owned MANY diesels over my life and this truck is a joy. I also own fast cars so this is not my beater so to speak. Yesterday after watching the 500 race I went into sport mode and nailed it and she went to 3800 and shifted, just like it does in D and eco mode. So I used the paddles and it goes to 3800rpm. Why does my tach say 4500 and why is it 3800 no matter what mode I am in?

Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old 02-22-2016, 03:16 PM
Member
My Jeep: 2014 3.0L
 
Join Date: Sep 2015
Posts: 23
Thanks: 0
Thanked 3 Times in 3 Posts
Rep Power: 462
biggiefl is on a distinguished road
Re: Max RPM question

So I assume this is normal since 80+ people have read it and nobody has posted "Hey mine goes to 4300 in sport mode."
Reply With Quote
  #3  
Old 02-22-2016, 03:48 PM
Member
My Jeep: 2015 3.0L WK2
 
Join Date: Feb 2014
Location: Tacoma, WA
Posts: 241
Thanks: 2
Thanked 23 Times in 19 Posts
Rep Power: 1257
MBDiesel is on a distinguished road
Re: Max RPM question

I don't think I've actually ever redlined mine since that's not where the power is on a diesel engine. Here's the dyno chart for the L630 (our engine) from the VM Motori site. Notice how power drops off considerably above about 4000 RPM.

__________________
2015 WK2 EcoDiesel Overland 4x4 Billet Silver, ORAII, ATG
1990 Mercedes-Benz 300D 2.5 Turbo - 155k
No sparks allowed!
Reply With Quote
  #4  
Old 02-22-2016, 04:16 PM
Member
My Jeep: 2014 3.0L
 
Join Date: Sep 2015
Posts: 23
Thanks: 0
Thanked 3 Times in 3 Posts
Rep Power: 462
biggiefl is on a distinguished road
Re: Max RPM question

"I don't think I've actually ever redlined mine since that's not where the power is on a diesel engine."


Hence why I am asking this at almost 15k miles. I am however curious if anyone is getting higher than 3800rpm as it does not make sense to have a 4500 redline on the tach if the engine only does 3800. I know with my 83 Benz you want to bring her up high every now and then to clear it out. These new diesels are so clean it probably is not the case and mine has NEVER gone into self-cleaning mode since i have owned it.
Reply With Quote
  #5  
Old 02-22-2016, 05:09 PM
akinney's Avatar
Member
My Jeep: 2015 3.0L WK2
 
Join Date: Jan 2015
Location: College Place, WA, USA
Posts: 223
Thanks: 68
Thanked 59 Times in 42 Posts
Rep Power: 16560
akinney has a reputation beyond reputeakinney has a reputation beyond reputeakinney has a reputation beyond reputeakinney has a reputation beyond reputeakinney has a reputation beyond reputeakinney has a reputation beyond reputeakinney has a reputation beyond reputeakinney has a reputation beyond reputeakinney has a reputation beyond reputeakinney has a reputation beyond reputeakinney has a reputation beyond repute
Garage
Re: Max RPM question

Quote:
Originally Posted by biggiefl View Post
"I don't think I've actually ever redlined mine since that's not where the power is on a diesel engine."


Hence why I am asking this at almost 15k miles. I am however curious if anyone is getting higher than 3800rpm as it does not make sense to have a 4500 redline on the tach if the engine only does 3800. I know with my 83 Benz you want to bring her up high every now and then to clear it out. These new diesels are so clean it probably is not the case and mine has NEVER gone into self-cleaning mode since i have owned it.
The intake manifold can get pretty oily/sooty, but I'm not sure if high revs are going to make any difference there.

I think the highest I've seen mine was about 3800, but I think this is a transmission mapping thing.

Have you tried the paddle shifters to see if you can go higher?
__________________
Deep Cherry Red 2015 JGC Ltd EcoDiesel with Beige Interior / ORA II / Lux II / 8.4AN
Mods: DEF injector guard | Mopar splash guards | Green Hornet fuel cap | Fumoto F-106 oil drain valve | aFe Pro Guard 7 engine air filter | Mopar molded running boards | Mopar roof rack cross bars | Mopar rear cargo net | Mopar rear cargo liner | Husky X-Act Contour floor liners | Mopar "Rugged Off-Road" Black & Machined 18x8 wheels
Reply With Quote
  #6  
Old 02-22-2016, 05:44 PM
Member
 
Join Date: Jun 2014
Posts: 44
Thanks: 7
Thanked 9 Times in 6 Posts
Rep Power: 941
timmy_ is on a distinguished road
Re: Max RPM question

From searching online, it appears our redline is 4500 RPM. I do not have any reason why the engine would not go faster than that prior to shifting. It is probably something to do with the programming in that just because you have a 4500 RPM does not mean you need to use it. By that point, the vehicle has produced all the power it can and is falling off. The same can be said about having a 140 mph maximum on the speedometer if the vehicle can't go past 121 mph.
Reply With Quote
  #7  
Old 02-23-2016, 09:44 AM
Member
My Jeep: 2014 3.0L
 
Join Date: Sep 2015
Posts: 23
Thanks: 0
Thanked 3 Times in 3 Posts
Rep Power: 462
biggiefl is on a distinguished road
Re: Max RPM question

Yes i have tried the paddles and it is like it just sits there at 3800 and no more. Not banging off the redline...just like being on a john Deere tractor.
Reply With Quote
  #8  
Old 02-24-2016, 03:27 AM
Member
My Jeep: 2015 3.0L WK2
 
Join Date: Feb 2014
Location: Tacoma, WA
Posts: 241
Thanks: 2
Thanked 23 Times in 19 Posts
Rep Power: 1257
MBDiesel is on a distinguished road
Re: Max RPM question

Quote:
Originally Posted by biggiefl View Post
Yes i have tried the paddles and it is like it just sits there at 3800 and no more. Not banging off the redline...just like being on a john Deere tractor.
That's how the governor on a diesel works. Granted ours is a software governor, but hit that RPM and it'll sit there just like a John Deere. No rev limiter cutting spark like gas motors do.

If you take your '83 Benz up to its (mechanical) governor, you'll see it'll just sit at 4800-5000RPM with the pedal floored as the governor reduces rack travel to prevent the engine from revving any higher.

I still have to ask, what's the point of revving over 3800? You're just about at the power peak and there's no extra power north of there with the stock tune.

I think the redline on the tach is only there to keep people happy who are used to seeing it. Notice the tach on your diesel Benz doesn't have a redline.
__________________
2015 WK2 EcoDiesel Overland 4x4 Billet Silver, ORAII, ATG
1990 Mercedes-Benz 300D 2.5 Turbo - 155k
No sparks allowed!
Reply With Quote
  #9  
Old 02-24-2016, 06:56 AM
f1anatic's Avatar
Premium Member
My Jeep: 2014 3.6L WK2
 
Join Date: Jan 2013
Location: Chicago, IL
Posts: 1,675
Thanks: 68
Thanked 184 Times in 137 Posts
Rep Power: 159924
f1anatic has a reputation beyond reputef1anatic has a reputation beyond reputef1anatic has a reputation beyond reputef1anatic has a reputation beyond reputef1anatic has a reputation beyond reputef1anatic has a reputation beyond reputef1anatic has a reputation beyond reputef1anatic has a reputation beyond reputef1anatic has a reputation beyond reputef1anatic has a reputation beyond reputef1anatic has a reputation beyond repute
Re: Max RPM question

Quote:
Originally Posted by MBDiesel View Post

I still have to ask, what's the point of revving over 3800? You're just about at the power peak and there's no extra power north of there with the stock tune.
Probably because like with any other car, automatic gear shifts are meant to happen AFTER the peak power for each gear. It is the area under the curve, not the peak value that matters most.
Reply With Quote
  #10  
Old 02-24-2016, 10:20 AM
Member
My Jeep: 2014 3.0L
 
Join Date: Sep 2015
Posts: 23
Thanks: 0
Thanked 3 Times in 3 Posts
Rep Power: 462
biggiefl is on a distinguished road
Re: Max RPM question

"I still have to ask, what's the point of revving over 3800? You're just about at the power peak and there's no extra power north of there with the stock tune."


Basically because I wanted to know ONE question.....IS THIS NORMAL?


All I am getting are questions for answers. Can anyone tell me "I get 4300" or "I get 3800 as well"?


What is so hard about this? For me an engine not running to or near redline means something is wrong. Now if it was a boat and the tach said normal redline operation is between 3600 and 4000 I would have no problem whatsoever with 3800. The fact my tach says 4500 I want to know if anyone is getting more than 3800.


Do I have to go to the dealer and go for a test drive to scare the salesman to find out this simple question?


PS--My Liberty CRD diesel would go to the 4k redline when nailed...right on the money.
Reply With Quote
  #11  
Old 02-26-2016, 10:18 AM
Member
My Jeep: 2014 3.0L
 
Join Date: Sep 2015
Posts: 23
Thanks: 0
Thanked 3 Times in 3 Posts
Rep Power: 462
biggiefl is on a distinguished road
Re: Max RPM question

348 views and not one reply as to what their GC redlines at?


Not sure if which is more pathetic, website or the Jeep owners.


Guess I am off to the dealership.
Reply With Quote
  #12  
Old 02-26-2016, 12:19 PM
Member
My Jeep: 2014 3.0L WK2
 
Join Date: Dec 2013
Location: Kerrville, TX
Posts: 617
Thanks: 59
Thanked 88 Times in 71 Posts
Rep Power: 1784
philbytx has a reputation beyond reputephilbytx has a reputation beyond reputephilbytx has a reputation beyond reputephilbytx has a reputation beyond reputephilbytx has a reputation beyond repute
Garage
Re: Max RPM question

Perhaps we all consider the red line as a WARNING and don't feel it necessary to find out what happens when we get there.

You will discover the redline usually if you screw up a shift or if you downshift at high speed. Remember, now we have software controlling our engines and also recording events.
__________________
Phil C.
2014 GC Overland 4x4, 3.0CRD, ATG, ORAII ("Smiffy")
2015 Lance 1685 Travel Trailer "#4"
2011 Kia Optima EX-L ("MC"
2003 BMW R1150RT "Darth"
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Overdrive & engine rpm question 402 Motoring Grand Cherokee - WK 4 03-09-2011 06:12 PM
Hemi RPM VS Penstar RPM erickpbl Grand Cherokee - WK2 - 4 12-25-2010 09:38 AM
99 WJ RPM drops! Andrew Engine Performance/Intake/Exhaust 37 10-30-2010 08:10 PM
Zero Oil Pressure @ idle but ok when over 2000 rpm's MALLOPPO Troubleshooting/Problems 3 02-22-2010 12:59 AM
superchips? issue maybe with rpm ryanwk Performance Modifications 4 10-30-2009 01:14 PM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 07:10 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community

JeepGarage.org is in no way associated with or endorsed by FCA US LLC. Chrysler, Dodge, Jeep, Ram, Mopar and SRT are registered trademarks of FCA US LLC.