Hi All,


My wife has a 2011 Dodge Nitro Heat 3.7 which is having an issue with the front differential. When driving - even very slow - it sounds like gears rattling together. When driving faster the car makes more of a growling noise (more of a wheel bearing sound). When the front wheels are off the ground, I can turn the propeller shaft back and forth and hear generally the same sound from the front axle. I am currently in the process of replacing wheel bearings, front and back, along with new CV axles and upper control arms (to replace the upper ball joints which are squeaking). None of these parts appear to be broken but the car has 218,500 miles on it, and it can't hurt to have new parts - right? Maybe a bad front wheel bearing is causing the front axle noise? It certainly sounds like something bad going on inside the front axle with the noise it is making. The differential gear lube level is right where it should be and appears to be very clean. I am not a mechanic and really need some advise on what to do with the axle. Rebuilding this axle is far beyond my ability. I am trying to determine if it is wise to just replace the front axle while it is all taken apart.


So here are some details and my actual questions: From looking at the axle and doing some internet research, I found that the axle is a Dana 30 K1 2003017 with a 3.73 gear ratio. I understand this is the light duty version of the axle due to it's K1 reference. I am having difficulty locating a K1 that does not already have 200k miles on it. I did however locate a Dana 30 K4 2003017 with a 3.73 gear ratio which is brand new and available at a reasonable price. I understand the K4 reference means this is a heavy duty version of the same build. My question is, can this K4 axle replace the existing K1 axle and are there any issues with fitment or negative performance? Can I assume that the K4 2003017 build will bolt on exactly the same? From all the pictures I have looked at it appears these are the same.


Thank you in advance for your guidance!

Rich

 

I wouldn’t be surprised if your noise was gone after CV joints and wheel bearings but it is possible that the carrier bearings in the front diff are making noise with that many miles. I have no idea if that means it’s time for a transmission or not…

 

Thanks for the reply. Update to the repairs so far. Rear differential drained and the gear lube looked pretty good as it also has 218k miles on it. Rear wheel bearings and seals replaced and they did not have any real noticeable damage or even any real wear. Front end is all taken apart and the new upper control arms are in. The wheel bearings and CV axles did not have any noticeable problems and everything moves smoothly by hand. I am still thinking there is something wrong in the front axle differential. Next step is to remove enough parts to get the front axle diff cover off an see what is going on inside there and why it sounds like gears rattling.

Still looking for an answer on whether or not the Dana K4 axle can replace the Dana K1 axle without any problems or modifications. Do you have anyone you can bring on to the conversation on that question? More detailed info is in the original post. Thanks in advance!

 

A shop manual would be your friend right now, do a google search and see what you can find.
if the diff is a bolt onyou should be able to determine if it needs bearings on the differential. I would pull the differential and take it with your new parts if it needs them to Qualified technician and have them do the work change the bearings. They must be pressed on and usually cut off and be over your pay grade.