UGGGHHH!!! Still front end knocking!!!!

[lfootmatt]

08 H3 Alpha 125K miles, Rancho 4" lift only lightly wheeled off road.

New outer diff bracket bushings, new cross member lower bushing, new front drive shaft, new CV joints/half shafts on both sides.

Still making noise.

On hard acceleration off straight line launch from stop or low speed roll it sounds exactly like a right front CV joint knocking. Replaced the right CV half shaft again, no change still knocking.

Ideas are welcome, I've been through this forum a bunch and don't see this one.

Thanks in advance!!!

Matt

 

[alrock]

Loose upper shock mount? Loose mounting bolts on upper control arm? Worn bushings in upper or lower control arms? Rancho crossmember bolts tight? Steering rack mounts tight on both driver and passenger side? Passenger side steering rack bushing intact?

Have you lifted the front wheels off the ground (one at a time is fine) and moved them side to side and up and down to check for any play?

 

[lfootmatt]

Sadly, it's in Lawrence, Kansas and I'm in Gilbert, Arizona. I'll forward this to my son's mechanic.

If that doesn't turn up anything I'll have him do the 4high lock remove front driveshaft trick and see if the noise persists.

Son is getting a new 2020 Silverado Elevation Edition, lifted, 33s, and exhaust...winning a Natty has benefits!!!
https://salina311.com/ncaa-national-champion/
So we'll be driving the H3 back to AZ for his little brother.

Thanks,
Keep the advice flowing!

Matt

 

[deserth3]

Not sure about the alphas. But the 3.5 liter had a cv joint on the drive shaft.

Sent from my SM-S906U1 using Tapatalk

 

[lfootmatt]

Brand new front driveshaft too. Would like to have it fixed prior to driving 1500 miles.

 

[alrock]

Wow, that's an awesome accomplishment for your son!

 

[lfootmatt]

Thanks! It's been a pretty awesome ride. He took the extra COVID year of eligibility. He's quite the fan favorite so his loyalty to Kansas paid off with both a National Championship and cashing in on his well earned name image and likeness!

And he's giving the H3 to his little brother, pretty sweet, just have to fix the orphan truck gremlins!!!

Matt

PS undergrad and Masters done, all on a full ride scholarship!!! Tires on the H3 we're my biggest college expense!

 

[lfootmatt]

What is the procedure to temporarily run with the front driveshaft removed?

Thinking of having him try that and see if the noise persists.

Thanks,

Matt

 

[H3Hummer]

What about your wheel hubs / Abs ? Mine were bad years ago and made like clunk noise at turning. Replaced both by AC Delo and no more truble since then.

 

[lfootmatt]

What about your wheel hubs / Abs ? Mine were bad years ago and made like clunk noise at turning. Replaced both by AC Delo and no more truble since then.

yeah, I suggested that but the mechanic said he did not think it was the wheel bearings.

We'll see, I just need to get it back to AZ then I'm not too worried about it.

Thanks,

Matt

 

[Jeepwalker]

I'm also leaning wheel bearings. H3's are kind of tough on wheel bearings if the tires are oversized. Even if they're not, if someone replaced the wheel hub/bearing with an import aftermarket, that could be part of it. I had to run along side my H3 while my wife drove ...to figure out a noise mine was making was coming from the bearing. You can push a long wood stick up to the hub while the wheel is turning (wheels up on jackstands) ...and put the other end of the stick to yer ear. If there's a failing bearing you can hear things grinding away inside (using the stick) and you can't otherwise hear. Give that a try. Doesn't cost anything to do, if he has access to jackstands.

If he doesn't hear the noise in the wheel bearings, move the stick over to the pumpkin and then to the pinion area.

 

[rascole]

What is the procedure to temporarily run with the front driveshaft removed?

Thinking of having him try that and see if the noise persists.

Thanks,

Matt

Remove the shaft, put in 4Hi locked and you're good to go. I have done it many times trouble shooting. What front drive shaft did you get? I had and O'Reilly's brand fail after 1 weekend trip. Upgrading the front drive shaft is easy and big upgrade.

 

[Jeepwalker]

I bought an AC Delco F driveshaft last summer. It's made by AAM (original equipment). There was an AAM sticker under the AC Delco foil sticker. Seems to be good quality. (Rockauto.com). Everything I've read these last about as long or better than most. YMMV. If interested, get one before they discontinue them.

 

[alrock]

When putting it in 4 hi lock for the purpose of running w/o the front shaft, do not have the truck running. Ignition needs to be on, engine off.

 

[Gpcalero]

The way I do it, is to put the truck in 4-high lock while its running. Go forward/reverse a few feet, then shut it off and then remove the front driveshaft.

Reminds me that I need to reinstall the front DS on my T actually lol.

 

[lfootmatt]

The way I do it, is to put the truck in 4-high lock while its running. Go forward/reverse a few feet, then shut it off and then remove the front driveshaft.

Reminds me that I need to reinstall the front DS on my T actually lol.

Thanks guys!

I'm having the mechanic pull the front diff cover and check it. Needs new oil anyway. I'll have him pull the front driveshaft and see if that makes much difference.

I just don't want to drive it 1200 miles, potentially through some mountains pulling a small uHaul unless it is right!

Thanks again!

Matt

 

[lfootmatt]

Okay, mechanic pulled the front drive shaft test drove it no noise. Front drive shaft had a bind on one side so they replaced that. Still have the thunk thunk thunk thunk noise on launch and hard from a slow roll.

He dropped the skid plate pulled the diff cover looked perfect.

Leaning towards a transfer case. Oh well I'm driving it from Kansas to Arizona on Saturday.

Pray for me!!!

Matt

 

[alrock]

Hope you don't have any issues. Maybe we can take a look at it when you're here. PM sent.

 

[EndeavoredH3]

You know, I had something like this happen with a cv axle from oreillys. Had a tough time getting it in and then on hard acceleration there was loud knocking.

Ended up swapping it out for an autozone cv and that’s been in since.

 

[lfootmatt]

alrock,

Thanks for the offer! That's the point of getting it back to AZ where I can work on it. Front end is pretty much all new bushings, half shafts (rt times 2), drive shaft (times 2), diff cover dropped and perfect inside.... Mechanic didn't think it was wheel bearing.

He did the front drive shaft removal and test drive. The thunking on launch went away. Found the new driveshaft to be binding on one side, thought we had it. Nope, still there after warranty replacement.

I'm leaning toward T case chain stretched and slapping.

Thanks all,

Matt

 

[H3Hummer]

So if no noise without the front drive shaft, did he check the U joints or CV's ? any play in it? It think the T case does not make that noise, real. If zhe T case had truble you would not be able to switch to High lock or Low lock.
For me, still going with bad front wheel bearings /hubs assembly. I remember that clunk on the passenger side of my H3 years ago, and i replaced the all assembly by AC Delco's. No noise since then.
A bad front or rear drive shaft will also make some bad vibrations with the noise , that's why i would check and change the front hub assembly.

 

[rascole]

Buy a cheap Gopro knock-off, add a magnetic base then put the camera in several different locations and test drive it. Look for a bushing moving when they shouldn't etc. I had a similar issue only in 4 Lo lock and it was the T case.

 

[H3Hummer]

Hollllly molllly, sound could be from your T case on that Moab clunk...... I would get it off and open, it's an easy job done and you can in the same job change your shift fork with the aluminum one !!!! It's a one big afternoon job.
Not to compare, but my old T case 4.16 from my Suzuki Samurai did the same clunk and after 3 days it was totally destroyed inside.

 

[rascole]

Hollllly molllly, sound could be from your T case on that Moab clunk...... I would get it off and open, it's an easy job done and you can in the same job change your shift fork with the aluminum one !!!! It's a one big afternoon job.
Not to compare, but my old T case 4.16 from my Suzuki Samurai did the same clunk and after 3 days it was totally destroyed inside.

It is an older video, swapped the case and problem went away.

 

[lfootmatt]

Well about the only thing not changed in the front end are the bearings. Here's to hoping they've got 1100 miles left in them. I'm driving it from Kansas to AZ Today.

Wish me luck!

Matt