In anticipation of my near future 12.5K fluid changes, I decided to
consult my owners manual and maintenance log again (it seems they
both don't give very much in the way of particulars though). 5/06 BD.
According to the manual, I really don't "usually operate" my vehicle
under schedule B conditions. How many of you "usually" do?

Have any of you ever really looked at the huge difference in
maintenance intervals? e.g.:

Drain and refill the front and rear axle fluid;
B = Every 12.5K
A = NEVER

Drain and refill transfer case, and ATF;
B = 62.5K
A = NEVER

Why is this? What should I do? What are you doing?
BTW, it seems other 4WD vehicles in the past have never
called for mandatory 12.5K diff. fluid change.
?HELP?
Your thoughts on this please.
Respectfully Submitted,

Bruno.....

I have the same concerns, Doc. Sure seems to be a wide range of interpretation on what seems right to do.

I changed everything soon after I got it and went synthetic throughout. For the next time around, I am looking at what has been standard for most of my vehicles in the past. I figure to change everything out again at about 30K. If I was towing ALL the time, maybe I would go with the 12.5K plan. I live on a gravel road in rural area with a wide range of weather conditions. I also use the Jeep off road a lot checking out my farm. I don't plan on being anal about changing the fluids each time the weather changes or I leave the road. The difference in the schedules seems to be to wide. A middle ground seems more prudent depending on what the Libby is used for. I will go for the 6.2K engine oil changes due to the conditions I operate, but am going for middle ground on everything else.

I am sure there will be many who disagree here, but I think a healthy dose of common sense and going with how your gut feels is in order.

Many people quote the schedule "B" as if it's the only schedule in the book. I don't operate under any of the conditions listed for it. I personally wouldn't change the diff. fluid unless they had gone under water. I will change the oil every 10k or so with a oil analysis every 2nd change or so.

Im going every 10K for motor oil changes, 5K on oil filter changes and a top off. The diffs are something I have never really worried about on other vehicles, for the CRD I am going to change it out at 12.5, and hopefully add RockLizads diff cover, I will probably change it again at 25K just to see what it looks like, if things look good, I will probably just wait until 50K to change it again, unless I submarine it, same goes for the front. Tranny will get a flush and new filters at 50K, then who knows when after that Maybe by that time DC will have a tranny fix worked out for us and I will get a free change then too Transfer case fluids will get changed at 50K and then whenever I remember to do it after that

_________________
It may be that your only purpose in life is to serve as a warning to others.

06 CRD Sport
Built 5/11/06
Jeep Green
Rocklizard diff cover
V6 Airbox

Get the good stuff from Amsoil and change every 100,000 miles. Ran the stuff in my last truck 277,000 miles even though I towed boats and overloaded it repeatedly on cross country trips. Nope I have no interest in Amsoil in anyway except as a customer.

_________________
No one knows as much as all of us.

Switch to good quality synthetics for your transfer case, diffs and transmission and worry about them less. Run the best oil & filter you can and pick a change interval that you are comfortable with. Using a oil analysis is a good idea if you are looking to extend your oil change intervals as it can give you info on how long of an interval is good for your particular engine based on your driving style, operating conditions, etc.
"Thanks Captain Obvious!"
Sure no problem, Your welcome!

_________________
99 TJ
71 C101
04 KJ
03 SFA KJ Sport
LOST JEEPS So-Cal

Please don't let your tranny fluid go forever and I'd even change it more than 62.5K. Chrysler transmissions don't have the best reputation and need all the help they can get with keeping the fluid fresh. I'd say every 30-40k if you are easy on it, more so if you tow alot. Chrysler just wants to get you outside the warranty and could careless if your vehicle fell apart afterward.

Also almost everyone is schedule B. According to the manual you are schedule B if you operate your vehicle under one or more of the follow:
Temp below 32F
Stop and go
extensive engine idling
dusty conditions
short trips of less than 10 miles
50% of driving at temps above 90F
Towing
Taxi, police, etc
Offroad or desert.

Sounds like pretty much every vehicle on the road.

I wouldn't worry so much about the diff and t-case. Just change the diffs and t-case every 30k with regular or 100k with synthetic. However, the engine and transmission are more import to keep an eye on.

The 90F is at sustained high speed. All the rest are if you usually operate at one or more of the conditions. If I get caught in a trafffic jam or idle the jeep at BK drive thru, that does NOT throw me into the schedule "B". Do as you like, but you are wasting dough. Quicky lube shops love people like you, they still shout 3k intervals for oil changes.
If you are schedule "B", then follow it, but clearly not every vehicle on the road is. These are robust machines and with normal schedule "A" maintenance will last far longer than the frame it's bolted to.

I had my tranny serviced at 30k by a local shop that I trust and have used for other cars. The owner reported that the fluid seemed fine, and that he saw a little metal in the pan and on the screens, but nothing beyond what would be considered "normal". I believe that the lesson learned is that if you are just leasing, or plan on dumping the car before high miles, don't bother with a 30k service. The manual shows a service only at 62k so not doing it wont involve any warranty problems.

I plan on keeping mine for a long time, if possible. So the money spent, approx $ 150, was worth it for the peace of mind even though my driving qualifies for the long interval service except when it gets cold here in New England.

Thanks everyone for your thoughts and info.
I will keep it all under advisement.
When I get the new diff. cover from Rock Lizard
I guess JJ will have to send me some oil (at cost, right?)
Then I can play it by ear.
Remember: An ounce of prevention is worth a pound of cure.

BTW: First engine oil change at 5700. Used Mobil 0W-40.
Picked up 50 RPM @ 70 MPH. (was 2000, now 1950).
I was pretty surprised. Checked it out over 300 miles.
This never happened to me before after an oil change.
See, you never know.

Bruno.....

I guess I am a rare one that is not schedule B........ 90 Miles a day, it always rains here(no Dust), I don't idle it very long, it is never above 90deg., etc. ...... Actually, I do think it is funny that people act like Jeep requires 12K or whatever oil changes in the rear diff. for everyone.

_________________
Feb/2006 Silver Sport 4x4 CRD

In the past I have been pretty bad about tranny fluid changes I guess with the rep that this tranny seems to be getting it would be a good idea to service it often. So I suppose I could get it done every 50K. Can you tell I like nice even numbers? 10K motor, 5K, motor filter, 50K tranny etc.. Thats stuff I can remember! Not this 12.5 on diff, 62.5 tranny, 6250 oil.

KISS... Keep It Simple, Stupid

_________________
It may be that your only purpose in life is to serve as a warning to others.

06 CRD Sport
Built 5/11/06
Jeep Green
Rocklizard diff cover
V6 Airbox

PM me and we will get you some good stuff.

_________________
99 TJ
71 C101
04 KJ
03 SFA KJ Sport
LOST JEEPS So-Cal

I've done two oil analysis' on my CRD; one with 5k on the oil (with 15k on the odometer) and one at 20k (with 10k on the oil). I'm using Amsoil 5w-40 European Formula. Based upon that, my initial conclusions are that this oil can go beyond 5k but just about reaches it's limit at 10k.

At 10k I had silicon (dirt) levels that warranted an oil change; TBN was also getting low. I checked my air intake system (regarding the dirt) and everything seems OK, so I'm thinking that maybe 10k is too long for the stock air filter. At any rate, my investigation continues. Next oil change (and analysis) at 6,250 per schedule "B".

If anyone is running 10k oil change intervals, I'd highly recommend performing routine oil analysis.

As for the other stuff, here's what I'm going to do:

Tranny and transfer case 30k.
Differentials 30k.

_________________
2006 Liberty Limited CRD Bright Silver Metallic (NOW SOLD)
All Recalls Performed
100k extended warranty
Fumoto Oil Drain Valves (Oil Pan & Transfer Case)
V6 Airbox Mod
New Driveshaft, New EGR
2003 Wrangler Sport 4.0L, Bright Blue
2007 Wrangler Sahara Unlimited 4 Door, Red Rock Crystal Pearl WOW!!!

Can you post up the actual results from your oil analysis?

_________________
99 TJ
71 C101
04 KJ
03 SFA KJ Sport
LOST JEEPS So-Cal

That is knida what I thought would be the suggested length of service time for oil in our Diesels...From another post:

Shell Rotella T (CJ-4) has been joined by Amsoil 5W-40 Premium Diesel Oil (DEO) with the CJ-4 rating. Both these are formulated for the newer 2007 emissions and soot control with ULSD.

These oils are both supposed to be able to keep the "soot" suspended in smaller molecules than lower rated oils (CI-4+ and down).

The newer (2007) emission standards have forced makers to employ EGRs that operate at higher (25%-35%) functioning rates. This means the newer engines run even hotter and require better protection than 2006 or older. The increased parameters on EGRs, Diesel Particulate Filters using the 15 ppm sulfur fuels (ULSD-which helps reduce particulate matter and works together with NOx reduction systems such as urea injection types) and the urea systems put different demands on our oils. The main thing CRD owners need to know is that the more an EGR is called on to work, the hotter the engine runs and less efficient it becomes.
It just makes sense that the CJ-4 rated oils will probably give us better protection.

The lower sulfated ash content (CI-4+ had 1.5%...the new CJ-4 is limited to 1%) will decrease lubricity and TBN to control alaklinity so new additives have been approved to reach the new CJ-4 rating. I think that this will lead to shorted drain intervals than the older oils (TBN has been decreased from 10-14 in CI-4+ to 8-9 in CJ-4). You can still do extended drain intervals but I wouldn't go the 25,000 mile route. I would suggest the 9,000-12,000 drain interval route with a new filter spun on every 3,000-4,000 and top off to bring back to correct level. Better safe than sorry.

_________________
Founder of L.O.S.T.
2006 CRD Sport
Mods: GDE Hot Tune w/ 364#@2000rpm/Air Box /3" Str8 Exhaust/ASFIR Alum Skids/245-75R-16 Cooper STT PRO/OME LIFT w/Clevis & 4 Spring Isos/AirTabs/Rigid 10" S2 LED/4xGuard Ctr Matrix Bumper
Drag Strip:Reac=.1078_60ft=2.224_1/8=10.39@64.8mph_1/4+16.46@80.8mph

Locked in high gear there is no way that the RPM would change at the same speed for any reason. unless you change gears or tires etc.

_________________
Feb/2006 Silver Sport 4x4 CRD