[dhh3]

I called my dealer for a quote for the 30,000 mile check. I have an advisor assigned to me. During our conversation, I asked him if there would be a price difference on the QDII axles. I heard him scream to another advisor - "What is QDII?" At that moment, I decided to take it to my local independent Goodyear shop. My Jeep dealer quoted me minimum 600.00 - they want 300.00 just to change the plugs! Here is my dilema. The owners manual says both axles take Mopar Synthetic Gear & Axle Lubricant SAE 75W-140 (API-GL5) or eqivalent with friction modifier additive. The manual does not break it down between QDII and the standard axles, so they both must take the same. The Goodyear shop called my dealer and gave them my VIN number and they told him to add the friction modifier to the back axle, but not the front. Do I need to take it back on Monday and have them add the friction modifier to the front axle? Thanks for listening. Oh, the total bill was $323.12, and they balanced/rotated tires! I apologize for posting this twice, but I really need some advice on this. I purchased an extended warranty, but I do not want to ruin my front axle. Thank you.rangehat:

 

[07JeepXK]

If you have QD II then yes you need the additive in both front and rear axles. QT II then just the rear.

 

[kidwired]

I have quadra-trac II, but there open diffs why would I need a friction modifier?

 

[07JeepXK]

I have quadra-trac II, but there open diffs why would I need a friction modifier?

The dealer told me that we have some sort of viscous coupler? in the rear axle and thats why we need friction modifier additive in the rear end. Who knows. Honestly I dont think they know what they are talking about. I think I might call around to a few other dealers and get their input. When I talked to my dealer the other day they didnt even know that the 2008 and newer 4.7 liter commanders had 16 spark plugs and not 8 spark plugs like my 2007 4.7 liter commander. I swear I know more about the commander then the guys at the dealer.

 

[kidwired]

hmmm, the viscous coupler is a function of the t-case. if you have QDII then you have ELSD and could benefit from additive. but really it shouldnt be required. Friction modifier simply softens the engangement/release of the locker. I have Detroit and trutrak in my YJ and use no modifiers, I like a "solid" engangement. no problems in 10yrs, other than broken axle shafts on the Rubicon trail.

Guess I need to see inside an open diff, I expect to see a regular R&P and spider gears.

 

[HueyPilotVN]

This is what you should see if you remove your rear diff cover. The metal skidplate at the top is for my extra gas tank, but the pumpkin should look like this one.