SO the other day I was going home from work, it was snowing pretty bad and the roads were really slick and crappy so I popped the ole girl in 4x4 just for added reassurance. On my commute I have a nice 90* turn that is completely blind till about half way through the turn. Well I get to that half way part, and this grey toyota carolla was spinning and fishtailing all over the place out of control, SO I did what any reasonable 23 year old in a big 4x4 cummins would do and drove right into the front yard of some guy who lives on that corner, I drove in, drove out and kept on my way. Ran over a few rocks and such but all was good, So I thoight.

 

I got about another 1/2 mile up the road when "crunch" "snap" "bang" happen. Not sure what was going on so I popped er out of 4 by go and all was good again. Got home and in the parkling lot of our apartment I put it back in 4 by. Drove a little and when I started to slow down there was the noises again. I checked my u-joints they are all good. I believe something inside under that diff cover is broken, loose, falling apart ect.

 

SO any ideas what it could be? I have not had a chance to pull the cover yet. And with the snow just a coming non-stop the past few days I would really enjoy having 4x4 again lol

 

Thanks

Just to make sure, check the vacuum lines and make sure they're all connected and not rotting off. One of mine dry rotted this fall and the drive line would make awful noises when you'd try to engage 4x4. Also, check to make sure you are in 4x2 or 4x4 and not "in-between" the two selections, that will make a grinding noise.

I did make sure I was in 4x4 and not in between. I didn't think about the vacuum lines. But would that cause the like "snapping" noise Ive got?

If it doesnt have enough vacuum then the axle disconnect cant move over and fully engage

I had a similar problem my 4x4 went in/out, the vacuum shifter thing (cant remember the correct name) went out, replaced the part and all is good again, I got tired of chaining up the back wheels, but got real good at it. One thing I learned is the when the 4x4 light is on the vacuum shifter has shifted the axle fork in place to connect the drive line to the axles assuming nothing is broken.

No 4x4 light no 4x4. So check to see if the light is on or off, it really does indicate something happening.

If the vacuum is bad the transfer case can think its in 4x4, but the front axle may not be engaging. Light for 4x4 comes off the transfer case.

4 x 4 light is on. Now if the vacuum shift iss failing would it create a constant, when in 4 wheel, problem or only on De acceleration?

 

My issue only seems to happen when I am slowing down.

 

Last night when I got home I crawled under the truck and spun my front drive shaft and heard an awful grinding noise coming from inside the differential. Not sure if this helps but it was pretty bad.

Time to do a inspection of the front differential and the CAD unit.

what is the CAD unit?

what is the CAD unit?

That is the axle disconnect. It is on the right side of the front axle and held in place by four bolts, real easy to inspect.

Edited February 12, 201411 yr by MnTom

What am I looking for inside there? Any thing in particular?

I just pulled the center axle disconnect and looked in there, nothing is broken or missing. The fork looks good and the ring gear moves freely and is not broken, cracked, or damaged in any way.

 

What all is involved in changeing a ring and pinion gear? Ive pretty much concluded it is something in that aspect.

The first thing you need to do is pull the cover and see what the problem is. You may or may not need a ring and pinion. Look at the spiders and see if there is something that just may be easier to fix.

That was the plan for either tonight or tomorrow. Ive got drill tonight so depending on how work goes, I may o r may not have time in between to pull the cover and look. The front end rebuild is pretty pricey, hopefully it's just something simple.

Well I just pulled the cover and Holy Moley! Not a drop of oil in er. I have a leak with out having a leak? :banghead:    My pinion bearing is toast. Not sure what else is bad untill I am able to pull the carrier out. My ring gear and pinion gear look okay, no cracks, breaks, chips or pieces missing. I'm gonna order a master overhaul kit for the Diff (bearings, seals, races, bolts, ect). 206 bucks from Rock Auto. That way I can replace it all while it's out. Never done one so this should be fun.
 
Any tips or pointers?

 

 

Here's what it looked like inside  :banghead: :banghead: :banghead:

Edited February 13, 201411 yr by MoparDave68

Looks clean. Lol. Sorry about that! Mine were low, but not dry. Frequent inspection needed. Pull the plugs and check fluid level takes maybe 5 minutes.

I'm interested in how doing it yourself works out. I've watched videos on chNging axle seals. Right side looks harder than left. Need special tool that's like $100. YouTube will get you started.

Edited February 13, 201411 yr by joecool911

I used to check em every oil change and I got away from it. I will neve forget to keep that inspected now. Big mistake that could of cost me a lot more damage than it did. I'm glad it's as clean as it is especially knowing that Ive been running with out oil for who knows how long! LOL. Well glad I caught it. Now to get it fixed!

The only thing that saved you was the CAD unit. The front drive-shaft does not turn full speed when in 2wd. Luckily you caught it before you really needed it!

Yeah I am very lucky. I checked everything over today, refilled it and spun the driveshaft. It sounds a million times better but I really need to get that bearing replaced now and find out which seal (s) are leaking and stop my fluid lose! lol

Look like you going to rebuild you front axle. (Seal and bearing kit)

If I was near my storage unit, I would takes pics for you to show you how I do seals. Its easy to knock the seals out and replace the driver side seal. Getting the passenger side one on is trickier.

 

You need a 4' long piece of 3/8" all-thread. Some fender weashers, piece of PVC and some nuts for the all-thread. The PVC needs to match the inside diameter of the seal. You will have to grind the edges down to fit inside the seal area. Use the nuts and washers to hold it in place. Clean the contacting surfaces where the seal is seated. Pre-lube the seal and contact area with gear lube.

 

Drive the seal into place going from the drivers side towards the passenger side. You will need a buddy to either hold the seal, PVC in place or using a sledge hammering on the end of the all-thread. You will have to go through the CAD to access the passenger side seal.

 

You will have to remove the gear unit to do all this, BTW.