Go Back   Jeep Garage - Jeep Forum > Jeep Platform Discussion > Grand Cherokee - WK

Join Jeep Garage Today
Reply
 
Thread Tools Display Modes
 
  #1  
Old 03-09-2011, 03:54 PM
402 Motoring's Avatar
Member
 
Join Date: Mar 2010
Location: Jackson NJ / Avon NJ
Posts: 152
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1778
402 Motoring is on a distinguished road
Overdrive & engine rpm question

So I just picked up an 05 5.7 Limited with 110K the other day and looks like I may already be experiencing some transmission issues. I mostly do hi way driving and I notice that at 65 mph my engine rpms are up in the 2K range. This seems a little high to me. To the guys with this same setup what are your rpms showing?

Thanks in advance.
__________________

__________________
Reply With Quote
  #2  
Old 03-09-2011, 04:05 PM
Long Live the Graphite Ghost

 
Join Date: May 2009
Posts: 13,417
Thanks: 55
Thanked 132 Times in 114 Posts
Rep Power: 542602
robpp has disabled reputation
Re: Overdrive & engine rpm question

i have the same trans and rear. Iwant to say at 75-80 i am just over 2k rpms.

545RFE, AUTOMATIC MULTI-SPEED
Three planetary gear sets, one overrunning clutch, with Electronic Range Select (ERS) driver interactive control, electronically controlled torque converter clutch.
Gear ratios:
1st - 3.00
2nd - 1.67 (upshift), 1.50 (kickdown)
3rd - 1.0
4th - 0.75
5th - 0.67
Rev - 3.0


Axle: - 3.73

Final Drive Ratio: 3.73 with 4.7-liter or 5.7-liter engine

Overall Top Gear: 2.50 with 3.73 axle
__________________

__________________
Reply With Quote
  #3  
Old 03-09-2011, 04:08 PM
402 Motoring's Avatar
Member
 
Join Date: Mar 2010
Location: Jackson NJ / Avon NJ
Posts: 152
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1778
402 Motoring is on a distinguished road
Re: Overdrive & engine rpm question

Yes and it has the Quadra Drive II transmission.
__________________
Reply With Quote
  #4  
Old 03-09-2011, 04:24 PM
Long Live the Graphite Ghost

 
Join Date: May 2009
Posts: 13,417
Thanks: 55
Thanked 132 Times in 114 Posts
Rep Power: 542602
robpp has disabled reputation
Re: Overdrive & engine rpm question

Quadra Drive is the 4wd system. it is the top of the line 4wd system, there are 3 of them. you have Electronic Limited Slip diffs.

545re something or other is the trans.



you can get more info about the wk than you ever need at www.wkjeeps.com
__________________
Reply With Quote
  #5  
Old 03-09-2011, 06:12 PM
Member
My Jeep: 2006 5.7L WK
 
Join Date: Dec 2009
Location: Home of the Mountain Blue Bird
Posts: 991
Thanks: 0
Thanked 19 Times in 17 Posts
Rep Power: 154894
jeepgcoman has a reputation beyond reputejeepgcoman has a reputation beyond reputejeepgcoman has a reputation beyond reputejeepgcoman has a reputation beyond reputejeepgcoman has a reputation beyond reputejeepgcoman has a reputation beyond reputejeepgcoman has a reputation beyond reputejeepgcoman has a reputation beyond reputejeepgcoman has a reputation beyond reputejeepgcoman has a reputation beyond reputejeepgcoman has a reputation beyond repute
Re: Overdrive & engine rpm question

In the 63-65 mph range you're right near the stock shiftpoint from 4th to 5th, and both are overdrive gears. With stock size tires, if you're in 4th, you'll be ~2200 RPM, and 5th you'll be ~1900 RPM. For me, living in hilly terrain, it's just about perfect if I drive at 63-64 mph. On level ground I goose it a little and it shifts to 5th. On inclines I backshift it to 4th and then back to Drive. This allows maximum use of the MDS, as many times on slight inclines the MDS will be off if in 5th, but will come on if in 4th (Drive). Also, be aware that with MDS active it will add ~50-125 RPM. When it comes out of MDS the engine RPM drops the same ~50-125 RPM to match turbine speed, if locked. The converter lock also plays a part here. It is not on when in MDS mode, but will come on, sometimes simultaneously, when the MDS kicks off. Bottom line, in this speed range, you should notice quite a bit of RPM shifts (could be mistaken for "hunting"), depending on the amount of hilly terrain, wind, etc., and yes, even type of road surface. I've seen up to about 4% change in engine load when changing from one type of road surface to another....i.e asphalt to concrete, or vice versa. This will also affect the MDS, which is load sensitive, among other parameters.
__________________
05 LX/RT & 06 WK/GCO, modded similarly, MDS "ON" Light, Vortex Gens, Debadged, DashHawk, BT Catch Can, SRT CAI W/Add Air Inlet, K&N Filter, Sonnax Trans Press Booster, SC Tuner W/Adv Trans Tuning App, DS Tuner, Cust tube headers w/3 in. catback, Bilsteins, SRT frt/rear bumpers, Eibach SRT Lwr Sprgs & Sways, FRI Sidewinder Cam Adv 2*, 6.1 valvetrain, SLP 25% UD Pulley, BBK 90mm TB, SOS Coils/.060 plug gaps. 20 in. SRT Reps.
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
Hemi RPM VS Penstar RPM erickpbl Grand Cherokee - WK2 - 4 12-25-2010 09:38 AM
Question for the engine guys paui4m Grand Cherokee - WK2 - 8 11-24-2010 12:41 PM
overdrive baronvonhavok Engine Performance/Intake/Exhaust 12 08-30-2010 01:10 PM
overdrive annoying andy.spf Engine Performance/Intake/Exhaust 5 01-07-2010 10:26 AM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 04:30 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community