Drivetrain Question

[wavemaker]

I have a 2006 Silverado 1500 HD. Recently it has started to make a rubbing/ grinding noise from the front left wheel area. It only makes the noise while coasting in four wheel drive. I won't have a chance to take it to a shop for a few weeks. Any ideas?
Thanks, Aaron

[Wild&Free]

my 04 does this sometimes when turning in 4wd.

does it make the same noise when 4wd is off?

[Steve07]

What kind of mileage? Autotrac 4wd?

[wavemaker]

about 230000 km. I don't know what autotrack is. It makes no sound in two wheel drive. It also doesn't make any sound in four wheel when the gas is pushed. Only when coasting.

[Steve07]

Does it have a big round button to push that says "Auto" on the 4x4 selector? Or just 4H, 2H, 4L?

[wavemaker]

Yes it has an auto button.

[backpacker]

Sounds like your hub locks are on the way out.

[Fisherpeak]

Do you shift into 4x4 while moving?I have a `99 Silverado with 400,000 ,never shifted into 4 wheel while moving and never had a problem.It has the auto button too,never used it either, just the 4 hi and 4 low button.

[sillyak]

Do you shift into 4x4 while moving?I have a `99 Silverado with 400,000 ,never shifted into 4 wheel while moving and never had a problem.It has the auto button too,never used it either, just the 4 hi and 4 low button.

Shifting into 4 hi on the fly below highway speeds does nothing to hurt a modern t-case.

Your issue could be a number of things. I would check the u-joint and front driveshaft. Although u-joints and cv joints usually make noise under acceleration and stop when you let off the gas, you never know and they are easy to check and change.

[Mekanik]

Although u-joints and cv joints usually make noise under acceleration and stop when you let off the gas, you never know and they are easy to check and change.

Usually. The one i'll be changing in a couple of hours is a clicking noise heard at low speeds with suspension travel and a vibration at higher speeds. Worn joints make the noise you're referring to.

I'd guess based off of what he says he's hearing is side bearings in the front diff assembly. Without being there to hear the noise, however, diagnostics like this are oh so fun and purely speculation.

Get them checked out.

[wavemaker]

Thanks for all of the ideas. I will get it in as soon as I can.

[CanuckShooter]

When I owned a silverado the front hubs would need replacing...had to do three of mine...they just replace the whole unit and charge you big bucks.

[DiabeticKripple]

if it was hubs and ujoints and stuff, wouldnt it happen all the time?

if it only happens in 4wd wouldnt it be t-case?

[jvillads]

When I owned a silverado the front hubs would need replacing...had to do three of mine...they just replace the whole unit and charge you big bucks.

X2 had to do the same with my 2006 1500 silverado.

[cody c]

I didn't know they had auto locking hubs, sounds like the hub though, the modern ones use an un rebuildable "unit bearing" hub in the front, many folks prefer the older style. Put the front end up on a jack stand, spin the tire and see if you can identify the sound, it could also be a U joint, hard to tell unless you get the axle shafts in your hand, though sometimes you can visually see they are rusted worn out when they're really bad.

[wavemaker]

So I was able to take my truck in to a shop today. After a short test drive the mechanic came back and told me that I need a new front differential because the bearings are shot. As well the mechanic told me that my exhaust manifold is cracked. He said that the only reason that an exhaust manifold cracks is because of a plugged catalytic converter. He suggested that I will need to replace both of my catalytic converters and my mannifold. After I left I called a transmision shop and the man I spoke to said that the bearings almost never fail on newer truck and that with the symptoms that I desribed he thought maybe a u-joint. He thought that if the bairings were bad on the diff that they would make noise in two or four wheel. I will try to get into the transmision shop over the next week and let them look at it. The rebuilt diff installed is about $2100.

[Dacotensis]

So I was able to take my truck in to a shop today. After a short test drive the mechanic came back and told me that I need a new front differential because the bearings are shot. As well the mechanic told me that my exhaust manifold is cracked. He said that the only reason that an exhaust manifold cracks is because of a plugged catalytic converter. He suggested that I will need to replace both of my catalytic converters and my mannifold. After I left I called a transmision shop and the man I spoke to said that the bearings almost never fail on newer truck and that with the symptoms that I desribed he thought maybe a u-joint. He thought that if the bairings were bad on the diff that they would make noise in two or four wheel. I will try to get into the transmision shop over the next week and let them look at it. The rebuilt diff installed is about $2100.

Have you gone to a wreckers to check their price?
Really should check that option if it comes to that!

It's no secret I'm shopping for a truck.

I talked to a mechanic who was selling his 2004 2500.
He told me that due to bad motor mounts, he ended up replacing the exhaust as the vibration cracked the manifold.
I think this is something to talk to a shop about wherever you decide to take it.

I don't know about the noise and the diagnosis of a bad diff

I would be leaning toward checking the left side where the noise is coming from.

More than likely your hub/bearing or your outer axle.
Those would be the first couple things I would look at.

Edit. If I needed to pay for two cats then I would bypass/ remove and run without.
This could be an issue at a later date if you wanted to sell.

[sako1]

So I was able to take my truck in to a shop today. After a short test drive the mechanic came back and told me that I need a new front differential because the bearings are shot. As well the mechanic told me that my exhaust manifold is cracked. He said that the only reason that an exhaust manifold cracks is because of a plugged catalytic converter. He suggested that I will need to replace both of my catalytic converters and my mannifold. After I left I called a transmision shop and the man I spoke to said that the bearings almost never fail on newer truck and that with the symptoms that I desribed he thought maybe a u-joint. He thought that if the bairings were bad on the diff that they would make noise in two or four wheel. I will try to get into the transmision shop over the next week and let them look at it. The rebuilt diff installed is about $2100.

This guy is feeding you a giant load of crap.

[Mekanik]

After I left I called a transmision shop and the man I spoke to said that the bearings almost never fail on newer truck and that with the symptoms that I desribed he thought maybe a u-joint. He thought that if the bairings were bad on the diff that they would make noise in two or four wheel. I will try to get into the transmision shop over the next week and let them look at it. The rebuilt diff installed is about $2100.

Toyota tundras, 2007-2010 have a bulletin out for side bearings in their front differentials. Noise goes away in 2wd as that set up has reduced load when not being driven. It's not as rare as one would think.

Find someone with a set of chassis ears. Most mechanics are deaf because we're too proud to wear ear protection when working.

This guy is feeding you a giant load of crap.

Which one? The guy who found a cracked manifold due to plugged cats or the transmission shop guy who just talked someone into his shop?

And if the transmission guy says something different ....

[wavemaker]

So I it is the side bearing does the diff need to be rebuilt? Can I drive for a while till I get it fixed?

[Dacotensis]

So I it is the side bearing does the diff need to be rebuilt? Can I drive for a while till I get it fixed?

Find an existing one from a wreckers in the city.

If it needs to be rebuilt, I would recommend Kendale truck parts.

They built my Auburn rear diff 2 years ago.
Otherwise look at a used one for a plug and play.
Or look on kijiji for a part you need.

There are ways to cut your costs.

Good luck

[coolpete1]

So I it is the side bearing does the diff need to be rebuilt? Can I drive for a while till I get it fixed?

i wouldn't leave it too long , bearings are cheaper than gears if the bearing comes apart the gears will likely be damaged . noise is there in 4wd because sometimes its more noticeable under load. you could leave the manifold for a while and if the cats are plugged you should have a catalyst efficiency code and the engine light should be on . for the diff i'd go to some place like pro trac gear , parts will be cheaper and they know what they're doing.

[Mekanik]

i wouldn't leave it too long , bearings are cheaper than gears if the bearing comes apart the gears will likely be damaged . noise is there in 4wd because sometimes its more noticeable under load. you could leave the manifold for a while and if the cats are plugged you should have a catalyst efficiency code and the engine light should be on . for the diff i'd go to some place like pro trac gear , parts will be cheaper and they know what they're doing.

Wavemaker - we're mechanically trained/minded, not fortune tellers and my crystal ball's in the shop. I have not heard the noise but from the information you've given us, there are still a lot of options. I agree with coolpete, it's usually cheaper the sooner you fix it.

the cats causing the manifolds to crack is a stretch for me. Sounds like something mythbusters should try since, as pete pointed out, the engine'll run pretty bad before steel gives up to air pressure. Or gaskets will fail.

[wavemaker]

Thanks for all the wisdom. I will make some calls tonight. How hard as a diff to change? I am fairly mechanical but I have never done one.

[Dacotensis]

You could change it. If you don't mind laying on the ground, it's possible to do in your driveway.

Unbolt your drive axles and driveshaft and have at it.

[rwm1273]

So I it is the side bearing does the diff need to be rebuilt? Can I drive for a while till I get it fixed?

Not very long. Buddy and I went hunting this fall in his truck, and the truck started to make some noise coming out of one spot. We thought it was a rock in the disk. Stopped and cleaned out the disk of the little bit of mud. Drove another couple KMs and the noise was back. Crawled under pulled a rock from the front drive shaft. Drove a couple more KMs and the noise was back. I was out and walked with the vehicle watching for anything indicating the problem. He would drive a few feet, and there would be a noticeable movement in the front wheels with a grinding noise. Then it all seemed to bind up and not move without lots of gas. We ended up getting it towed back to the closest town.

He had just had his front U joints replaced and an seal replaced on the front diff. It appears they didn't put in enough oil, and it caused the bearings to fail. He got it repaired under warranty, but cost him lots for car rental while it was in the shop.

On my truck, the pinion bearing was making noise. I initially thought it was an axle bearing, and changed both axle bearings. When I had the diff cover off the gears look ok. So after a couple months of the noise still there, I took the diff apart, and found the front pinion bearing pitted, and now so were my spider gears. I changed the whole diff carrier and clutch packs for about $400, and new bearing all around. Cost about $600 with oil, bearings, and knew diff assy. Took me about 3 hours to r&r the assy in my driveway.

[wavemaker]

So I had two places tell me it was the front diff so I replaced the front diff. The problem was still there. The transmission shop that did the diff then said that it is the transfer case. I had this rebuilt last year so I took it back to the shop that had rebuilt it. They took the transfer case apart and replaced the bearings and seals. The sound is still there. Nobody seems to have a solution. This is getting expensive. Any ideas?

[sako1]

So I had two places tell me it was the front diff so I replaced the front diff. The problem was still there. The transmission shop that did the diff then said that it is the transfer case. I had this rebuilt last year so I took it back to the shop that had rebuilt it. They took the transfer case apart and replaced the bearings and seals. The sound is still there. Nobody seems to have a solution. This is getting expensive. Any ideas?

HOLY COW!! Sounds like some real bad advice from some real bad shops.

[leeaspell]

Why not take it to the dealership. They work on those trucks day in and day out. They probably know exactly what the problem is, seen it thousands of times.

[Fordpilot83]

Have the dealership drive it. With all that reapired id say get a value on it and trade it off. Gm and there i.f.s. is always causing problems

[elkdump]

I have a 2006 Silverado 1500 HD. Recently it has started to make a rubbing/ grinding noise from the front left wheel area. It only makes the noise while coasting in four wheel drive. I won't have a chance to take it to a shop for a few weeks. Any ideas?
Thanks, Aaron

when you get tired of dumping money into your 2006 Silverado, list here on AOF for sale,,,

first dibs,,, $1000 cash if it is a crew cab 5.3 V8, :)

[TimeOff]

Are you sure the L/H CV shaft is ok?. Does it make more noise while taking a corner?.
Also sometimes noise transfers through the driveline so it may be coming from another source. Had a bad rear diff feel like a fwd diff or wheel brg. Also with that milage check you're rear propeller shaft steady brg. Forward propeller shaft, though I'm sure the shop would have checked that when they did the fwd diff. Does it make the noise only in gear?. Check it in neutral when coasting down as well. Might rule out transmission and transfer case if it happens either way. Good luck.

[Mekanik]

Seriously? I honestly hope you haven't been paying for repairs that have not been repairing the original complaint.

Isolate the noise using chassis ears.

Inspect

Repair.

Verify.

I'd say a lot of guessing has already gone on.

[steve0]

I had a similar issue with my 06 Yukon XL, weird noises from the front in 4x4
For mine it was the actual 4WD Indicator Light Switch that was gone, it wasn't shifting properly and faulting so the truck didn't know to be in 4x4 or not or it wasn't properly engaging the 4x4

I replaced the 4WD Indicator Light Switch ($60 from Rock Auto) and the problem is gone. Its a known issue with GM's from what I could find out. And my 4x4 and front end are all good now!

[wavemaker]

I have been paying what I would think are discounted rates. I had the truck checked at a shop but they said that they could not find a used diff and would only install a rebuilt diff for about $2100.I found used diff with low km for $500 and Clutch and Grab installed it for just over $300. I went there from a family recomendation. When the transfercase oil was drained to check a small pin bearing was found in the oil. The Transfercase was a rebuild from Canwest Transmision that was installed last Jan. I contacted Canwest to see what they could do since the transfercase was just outside of the one year warranty. They did a lesser re-build replacing all of the seals and bearings for $500. I think that the shops that I have been dealing with are charging me fair prices. The problem is the way that I started the repair. Canwest had the truck for a few extra days and they couldn't find any problem with any of the drive train. They measured the tires and said that the front tires are 1/2 inch larger than the back ones. They say that this is the only solution that is left. This weekend I am going to swap tires with my neighbour to see if that is the problem.