Front end grinding in 2wd and 4wd full time

bmercer · **Joined:** Sat Aug 03, 2013 8:44 pm **Posts:** 9

Been searching most of the day but can't seem to find a suitable solution! My 05 with select-trac has a bad grinding noise from the front of the vehicle. Sounds like it is coming out of the front differential. Now, I replaced the entire front drive shaft a few months back.. it's good to go. That is not the issue.

I jacked it up and found that when I put it in 4wd full time the drivers side front wheel does not turn when you gas it, but the passenger side does. The really weird thing is, when i drive it, the grinding goes away in part-time and 4wd low. When I put it on the jack stands, i can hear the grinding in part time, and 4 low, but its nothing like full time...

Any ideas what this might be?

flash7210 · **Posted:** Wed Jul 19, 2017 8:43 pm

Here is how I test the 4wd system.
Assuming you do not have a 2006 with traction control.

Get all 4 wheels safely off the ground.
Start up the engine and put it part-time and drive. Both rear wheels should be spinning equally along with at least one front wheel.
Take a long 2x4 and from the front of the jeep slide it under the wheel that is spinning fastest. Lift up the 2x4 against the tire until you can almost get it to stop. While doing this, the front open differential will transfer power to the other wheel and it should pick up speed.
If this doesnt happen, then you have a problem inside the front differential.

This may also help you isolate the grinding noise.

I suspect that the grinding noise is from a bearing.
Could be a wheel hub bearing or one of the bearings in the differential case.
It wouldnt hurt to drain and refill the front diff.
Drain the oil into a pan and shine a flashlight on the oil. If you see shiny glitter in the oil, that would be a clue.

bmercer · **Joined:** Sat Aug 03, 2013 8:44 pm **Posts:** 9

Thank you for the quick response!

The passenger side was spinning the most, so I put the 2x4 on it and the grinding sound got REALLY bad, the other wheel picked up a little speed but not much. After taking off the tire and rotating just the passenger side, that is where the grinding is coming from. The drivers side feels fine and smooth when I spin it. The passenger side is very rough. Feels like its just skipping over teeth inside the differential if that makes sense (don't know all the fancy mechanic terms).

It feels like its a bearing inside the differential if anything... I will drain the fluid tomorrow and find out...

One more thing - would it be possible for me to take off the passenger side axle altogether and run it to see if the grinding stops? That might help me narrow it down even more. But I don't want to tear up the differential any more than it probably already is.

bmercer · **Joined:** Sat Aug 03, 2013 8:44 pm **Posts:** 9

Tonight I pulled off the CV Axle shaft on the passenger side. Where the CV Axle shaft and Axle shaft connect, is completely worn down. I started it up and put it in 4wd full time. You can see the Axle Shaft (part # 05066057AB) spinning, and there is no more grinding sound. The Axle shaft also spins pretty rough, as in it looks like its a little bent. I am hoping just an axle shaft, and CV Axle replacement will do the job.

My question is... should the drivers side wheel be spinning if it is in 4wd full time? Or does it only power the 1 wheel as long as there is no resistance? There is definitely no resistance since the CV shaft is disconnected.

This may end up being a little past my experience level and I may end up taking this sucker to a mechanic to get the new Axle shaft installed. Or past the amount of time I have to spend on it. I should be able to drive it with it disconnected in 2wd to get it there. I am just worried there is something wrong inside the differential as well.

APC9199 · **Posted:** Thu Jul 20, 2017 11:13 pm

Where what connects to what? Where the CV half shaft connects to the wheel hub or where it connects to the front differential? I'm a little confused by your description. The CV half shaft connects to the wheel hub by splines on the end of the shaft and a 35mm (?) nut on the end. The differential end goes thru a seal in the differential housing and connects to an intermediate shaft in the differential, also by means of a set of splines. The intermediate shaft can usually be removed along with the CV half shaft (it usually comes out as one unit and is tough to get apart). The intermediate shaft has splines on the other end as well, to connect with the gears in the differential. Any of those sets of splines can be worn down as you describe, with the ones connecting to the intermediate shaft being the most common point of failure. Whichever one or ones is/are damaged will tell you what else you need to inspect. If the wheel hub splines on the CV are worn down, you probably need to also inspect the wheel hub to see what condition it is in. So on and so forth.

Furthermore, the CV half shaft itself can have bad CV joints which will cause problems, but you wouldn't be able to see it and describe it as "worn down".

Can you explain a little further with some part numbers from the service manual?

WWDiesel · **Posted:** Fri Jul 21, 2017 1:50 pm

Some pictures of the items you have observed that look problematic might also help.... :wink:

bmercer · **Joined:** Sat Aug 03, 2013 8:44 pm **Posts:** 9

Where it connects to the intermediate shaft. I was calling it the axle shaft as that is what the part description is on the Chrysler parts page. The picture is where the CV Shaft connects to the intermediate shaft. It looks like it has been ground down pretty bad.

I cannot pull that intermediate shaft out correct? It feels like it has a C-clip on the inside of the casing keeping it from coming out too far.

APC9199 · **Posted:** Sat Jul 22, 2017 11:52 am

It will come out. There is a wire clip that keeps it partially engaged in the differential. It might take a little coercing, but it will pop out. Usually they come out corrosion welded to the CV half shaft.

WWDiesel · **Posted:** Sat Jul 22, 2017 1:40 pm

bmercer wrote:

Where it connects to the intermediate shaft. I was calling it the axle shaft as that is what the part description is on the Chrysler parts page. The picture is where the CV Shaft connects to the intermediate shaft. It looks like it has been ground down pretty bad.

I cannot pull that intermediate shaft out correct? It feels like it has a C-clip on the inside of the casing keeping it from coming out too far.

Thats UGLY!!!! :shock:

Time for new a shaft! :wink:

You should be able to pop it out of the differential...

bmercer · **Joined:** Sat Aug 03, 2013 8:44 pm **Posts:** 9

SO there she is. Yup.. it's done for. New CV Shaft, Intermediate shaft on order.

Of course, I noticed my boot on my lower ball joint was busted and leaking so I have something to do while I wait!!

Thanks everyone for the help. Once I get it all in I will confirm if it fixed everything.

Front end grinding in 2wd and 4wd full time

Who is online