Transfer Case question / 2000 Jeep Grand Cherokee

In article , James wrote: # #This car has the Quadra Drive. It has 145,000 miles on it. # #I had the oil changed in this car today. The mechanic checked all of the #fluids, and found them all ok, except for the transfer case, which he said #was very low. He filled it up with Dextron III. My manual says this is #acceptable. Was the fluid totaly replaced? What color was the goop that came out? Yellow? Smells like vinyl?

Your manual is wrong. You need special (as in special education special) transfer case fluid only available from Mopar. P/N 05016796AAN. The recomended change interval is 22,550 miles. All NV 247 transfer cases came from the factory with 05016796AA starting on 4/9/99.

#The car immediately started making extreme noises as I drove it off. It #was clear that it had a major drive train problem. I drove it back to the #mechanic, who inspected it closely. He is certain the problem is coming #from the transfer case. He believes that the clutches are slipping, or the #chain is skipping. He says that the best remedy is to find a replacement #transfer case and switch it out. Yeah, it's possible that is what happened when you let your fluid run low.

The fact is that he put the wrong goo in and now it is broken. Make him fix it.

#This is a new mechanic to me, as I am on vacation at our vacation house. #But, I fully believe that the mechanic is honest and capable. But, I #have to drive this car 500 miles on Monday , and tomorrow is Friday, so this #is urgent to me. Find a dealership and get the right fluid. Put it in and dive some figure-8s to push the ATF out of the gerotor and any other nooks and crannies. Drain it and refill with more 05016796AA. Lather-rinse-repeat until you see no red in there.

#My son says that in spite of what the car manual says, that the transfer #case should be filled with ATF+3 or ATF+4 specified for Chrysler (not #Dextron III).

#Can you guys give me some input on this ? If I drain the Dextron III and #put in ATF+3, how likely would this cure the problem ?

Your son is wrong, but on the right track. 05016796AA is the stuff you need and it's only available from a dealer (from what I've seen). It is only used in the NV 247.

/herb

Worst case senerio, you could remove front drive shaft and lock Tcase and drive it home that way if it runs quiet that way and get it repaired at home later on.

----------------- TheSnoMan.com

James proclaimed:

It was driving until the mechanic added the fluid. It might have been low until he did that, but you did not mention any noise prior to him touching the vehicle. He may be honest, but he sure has no clue what he is doing.

This will be my last post on this subject.

I try to be fair and reasonable with people. I don't blame the mechanic. He insisted on looking at my Jeep manual, which says that regular ATF or Dextron III can be used in the transfer case. He used ATF. I think that was a reasonable precaution, to look at the book. After all, isn't that the most common admonition, RTFM ??

Yes, Jeep later decided that this particular transfer case needed another fluid, only made by Chrysler-Jeep. They did not mail this news to every human being in the world.

It would be easy to blame him, but in my opinion, unfair. Since this is my Jeep, I am the only one to make the call on this one.

James

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L It was driving until the mechanic added the fluid. It might have been low until he did that, but you did not mention any noise prior to him touching the vehicle. He may be honest, but he sure has no clue what he is doing.

Consider this though, you pay a mech to kinda do it right just like you pay a doctor to do their job right too. That aside, ATF would not have killed Tcase but rather it could have made clutches in it chatter some but it would not have been terminal. The specail fluid is simular the the purple fluid that GM uses in their automatic Tcases. (also known as syncomesh fluid)

----------------- TheSnoMan.com

SnoMan proclaimed:

At least two of the transfer cases have explicit clutches. All three of them note the number one cause of noise is the wrong fluid, and as someone else pointed out the cure for the wrong fluid is to drain and flush--with a teardown only being recommended if that doesn't cure it.

I would expect anyone hiring themselves out as a mechanic to check service bulletins in addition to a factory, not aftermarket service manual. Or just notice the noise on a test drive and go hit the service bulletins then--we all make mistakes. The owner didn't make the mistake, the mechanic did and asking him to deal with it does not seem overly harsh--unless the owner is willing to pay for the cost of repairs if actually needed. If it wasn't driven too far, my guess would be not.

? Dunno what book you are looking at, but my [95] FSM shows two of them with explicit clutches shown in the teardown and overview. Are the

Jerry Bransford proclaimed:

there is a small round tag on the bac of the t case near the drain plug and fill plugs that must be looked at if the tag has 231 or 242 on it dexron 3 is the fluid. if not then the mopar fluid must be used the other t case numbers are 249 and 247

Lon, I could be wrong on the JGC's t-case as I really thought it was a chain driven t-case as is used in most Jeeps. Maybe the Quadratrac or Quadradrive t-cases have a clutch but I thought they used a differential to provide for their full-time abilities.

Jerry

L> ? Dunno what book you are looking at, but my [95] FSM shows two of them

Not if it is a modern Qtrac that they offered as a option on some models.

----------------- TheSnoMan.com

Look before you leap. Qtrac version has a form of clutches in it to act like a LSD across center diff. The original Qtrac from 73 to 79 (and I still have one) used tapered friction cones in and tapered hub preloaded to act as a LSD and it too required a specail lube or additive to work properly. (actually the specail lube then was 20 weight non detergent oil with a additive) If you use wrong lube it could act funny and make strange noises especailly in turns.

----------------- TheSnoMan.com

I can see no "clutch" in the NP231 [2H 4H 4L N], there is a clutch shaft in the NP242 which appears to be part of the internal differential for the 4H full time [2H, 4H part time, 4H full time, 4Lo] the NP249 has a clutch sleeve [4H, 4L] with the viscous coupler and is somewhat fussy about fluid. Was surprised to see them mentioned as you are correct they are chain driven. All models have have the same diagnosis of noisy, not enough fluid or the wrong one.

Jerry Bransford proclaimed:

I didn't think the 247 was around in 2000.

---Greg---

Yes, my transfer case in my 2000 JGC is an NV 247.

James

In article , Greg wrote: #I didn't think the 247 was around in 2000. #

The 247 was first used in the 1999 model year WJ.

/herb

In article , SnoMan wrote: #Worst case senerio, you could remove front drive shaft and lock Tcase #and drive it home that way if it runs quiet that way and get it #repaired at home later on. #----------------- #TheSnoMan.com

The 247 is a full-time t-case. I removed the front shaft on a '99 WJ when the CV in the shaft lost it's grease and the thing started to rattle. It drove just fine. Mileage went up .5 mpg or so before I put in a greaseable u-joint shaft.

But with the wrong lube in the t-case, I don't know if any damage to the t-case will be avoided by removing the front shaft.

/herb

In article , Lon wrote: # #I can see no "clutch" in the NP231 [2H 4H 4L N], there is a clutch shaft #in the NP242 which appears to be part of the internal differential for #the 4H full time [2H, 4H part time, 4H full time, 4Lo] the NP249 has a #clutch sleeve [4H, 4L] with the viscous coupler and is somewhat fussy #about fluid. Was surprised to see them mentioned as you are correct #they are chain driven. All models have have the same diagnosis of #noisy, not enough fluid or the wrong one.

The OP's t-case is a NV247. It has a clutch that is engaged by a gerotor. When the front and rear shafts move at different speeds, the gerotor pumps fluid into the clutch-pack. This locks the two shafts so that the free spinning shaft stops spinning and the gripping shaft gets more power.

The OP's diffs also have gerotors and require a additive to the full synthetic gear lube.

What gets me is that the additive at the local autoparts store says it meets the DC spec # for the lube but then specificaly states that it's not for Jeeps with Quadradrive. GAh...

/herb