Hey Guys, I had a NEW Rear Diff installed under my MaxCare warranty... I have a 14 Polar JKU ... Stock rear was a Dana 44 4.1 . After picking up the truck last week it feels a bit different ,,, May be in my head.. Is there any markings on the Rear Diff to tell me what gear ratio is in the NEW unit? Thanks!!!!

 

As much as I hate dealers, I don't believe any dealer is incompetent to the point of installing the wrong gears unless you had for some reason previously regeared and not disclosed that information to them (they're pulling that build from your VIN). That however is not the case since you're getting that covered under warranty. The only things you can do if you want to confirm are 1) pull the diff cover off and count the ring gear teeth, or 2) jack up the rear end and count drive shaft rotations as you turn the tire a full rotation.

What do you think feels "different" about it? Out of curiosity, did they instruct you on a breaking period at all, or just send you on your way to jump on the interstate at 75mph?

 

Maybe it feels different because your old one needed replacing.....

 

Hi, thanks for your help! It was under warranty... They didnt say a word about breaking in either! Can u tell me the break in period? Went on the beach yesterday and 4WD was fine ... No noises etc .... I felt like it was in overdrive feeling ... Can u tell me the correct break in period? thanks again for your help!

 

Thats what my wife said !

 

Now this is the thing about a dealership that doesn't surprise me one bit. It's a bit late now, but you can google new gear break in. Basically, the first few heat cycles and general load over the first few hundred miles is important. They should have advised you to take some easy, short trips, let things cool down and repeat......not just jump in it and drive off like normal or go wheelin. It happens thousands of times a day I'm sure with no ill effects. Along same lines, people don't pull out of brake shops and then go bed their new pads/rotors, though it's good practice. Don't stress about it or anything.

 

If you ran it in 4wd and the transfer case didn't explode, then they put the correct ratio back in.

 

yes, this is very true indeed.