Odd sensation on acceleration from full stop

[camaroz2887]

Cv axel? Any clicks on hard turns? My original cv went bad and it was just doin the normal click click click... however the Napa axel that I replaced literally today was just starting to have the same sensation on acceleration only from a stop but it was also accompanied by a slight audible thud and the normal clicking as well.
You seem to be feeling it not hearing it though so I dunno. It might be worth a look though.

Good luck

On a side note the sound dampening in these trucks is pretty far above what I expected (though that’s not hard). I went into winter with very light clicking of the cv and forgot about it til spring! First time the windows went down I almost cried for letting it go on that long.

 

[jyi786]

Cv axel? Any clicks on hard turns? My original cv went bad and it was just doin the normal click click click... however the Napa axel that I replaced literally today was just starting to have the same sensation on acceleration only from a stop but it was also accompanied by a slight audible thud and the normal clicking as well.
You seem to be feeling it not hearing it though so I dunno. It might be worth a look though.

Good luck

On a side note the sound dampening in these trucks is pretty far above what I expected (though that’s not hard). I went into winter with very light clicking of the cv and forgot about it til spring! First time the windows went down I almost cried for letting it go on that long.

No clicks. Just clanks when going over bumps and with the wheels cocked to the left.

Do the simple stuff first. Check the swaybar end links, 4 rubber bushings on each side, 2 up, 2 down on each side.

Ok, so I went under the truck today. Still not sure what is causing it. I ordered new sway bar links, and am going to try to install them tomorrow. I identified and tightened up the bolts for the front differential mount, and it almost seems like it's clanking less, but I can't be sure until I drive it tomorrow.

Also, I'm a bit afraid now: I found what looks to be gear oil dripping out the rear end of the front differential, where it connects to the long transfer rod. What does that mean?

 

[PG01]

No clicks. Just clanks when going over bumps and with the wheels cocked to the left.



Ok, so I went under the truck today. Still not sure what is causing it. I ordered new sway bar links, and am going to try to install them tomorrow. I identified and tightened up the bolts for the front differential mount, and it almost seems like it's clanking less, but I can't be sure until I drive it tomorrow.

Also, I'm a bit afraid now: I found what looks to be gear oil dripping out the rear end of the front differential, where it connects to the long transfer rod. What does that mean?

Its just a seal, easy to replace....although if the seal is leaking maybe your front diff is starting to go out....common on awd models...depending on prior maintenance history....and that could be your clank.... fluid level could be low.... and that could be your clank... see where im going here?

 

[Doubeleive]

front pinion seal, replacing just the seal may not be so difficult but if continues to leak after that then the problem is deeper

 

[jyi786]

Its just a seal, easy to replace....although if the seal is leaking maybe your front diff is starting to go out....common on awd models...depending on prior maintenance history....and that could be your clank.... fluid level could be low.... and that could be your clank... see where im going here?

Yes, I do. Since I bought the truck, I've driven 66K miles. It only started doing this recently. I've serviced the front diff twice since I got this truck; when I did it the first time, 2.75 qts. or so came out; same this time, so I don't think the clank is because fluid is low. It's definitely mechanical.

front pinion seal, replacing just the seal may not be so difficult but if continues to leak after that then the problem is deeper

Yes, I'm getting consensus on this now. Pinion seal definitely.

I'm going to monitor it, and I'm also going to change the sway bar links tomorrow evening to see if it makes any difference.

 

[wjburken]

My first thoughts were the front differential is going. I would not think that a bad seal would cause a clunking sound. A bad bearing or low fluid might, but likely not low fluid if you have just recently serviced it.

One thing that can tear up a front differential as well as a transfer case on an AWD vehicle is if the tires are not all the same circumference.

Just confirm that your front tires are the same size and have the same amount of wear as your rear tires. I’m sure yours are but I’ve seen people, even dealers, try and save money by only replacing two tires on an AWD vehicle and end up tearing up the drive train because they have brand new tires on the front and worn tires on the rear, or vice-a-versa.

 

[jyi786]

My first thoughts were the front differential is going. I would not think that a bad seal would cause a clunking sound. A bad bearing or low fluid might, but likely not low fluid if you have just recently serviced it.

One thing that can tear up a front differential as well as a transfer case on an AWD vehicle is if the tires are not all the same circumference.

Just confirm that your front tires are the same size and have the same amount of wear as your rear tires. I’m sure yours are but I’ve seen people, even dealers, try and save money by only replacing two tires on an AWD vehicle and end up tearing up the drive train because they have brand new tires on the front and worn tires on the rear, or vice-a-versa.

Thanks for the suggestion. I myself have read horror stories about people using tire and wheel sizes that end up wrecking their drivetrains.

I can unequivocally confirm that's not the case with me. The wheels are all the same size, tires the same as well. I bought them from Tirerack, had them installed professionally, and have them road force balanced religiously every 7500 miles as specified in the manual. All tires show wear evenly and do not show any evidence of irregular wear patterns.

This is what is so confusing to me, because I was sure if something was going bad suspension-wise, it would have manifested itself at least on the left front tire, especially as loud as the clanking is now.

I'm really, really hoping it's the sway bar links.

 

[swathdiver]

Bad mounts could let the diff move too much which wrecked the pinion seal...

 

[jyi786]

Update: changed the sway bar links. Did not fix the issue. But the ride is considerably improved; the stock ones on there were completely trashed, dried out completely. It was like riding on stones. Front end doesn't jounce over bumps anymore and is completely smooth like glass when cruising.

I sent an email to my shop asking them how long and how much it would cost to change the diff mounts and the pinion seal.

 

[JimG]

I had a similar sensation in my 12 ESV last year. Turns out it was a collapsed engine mount for me. Fairly inexpensive correction.