pulsing and roaring when accelerating

[devynbradley]

I have a 2004 ford explorer and have had it for over a year. Just recently I put two new front tires on it and as soon as I drove off it started making a roaring sound.... It is not from the tires BC it is only doing it when I push the gas. In the past few weeks it has gotten worse and has added a pulsing to it upon acceleration. We have no idea what this is and or what it possibly could be. The transmission seems fine as it is not slipping or raising the rpms. It does it off and on so it isn't constantly doing it. Usually does it at least once a day . any input would help. Thanks

 

[FR-425]

Sorry that's just not enough information for anyone to eve take a guess. Depends on what you mean Pulsing? roaring? these are not descriptive enough. Backfiring, hesitation, knocking.?

Not trying to beat you up here but your saying, Hey guys my truck makes a noise any ideas? Yea, you got a noisy truck. give us a little more info an d maybe we can help.

 

[devynbradley]

I appreciate you responding but please excuse me for not giving enough info I am not a mechanic so in result I do not know all the details to give....


2004 Ford Explorer V6
Had for a little over a year.
I put new tires on it on November 7th 2013 and this is when I started hearing a roaring or humming noise every now and then but ONLY when pressing the accelerator. It does not do it all the time. I do not know where it is coming from but you can hear it from all seats in the vehicle when driving down the road. It does not do it when idleing. Again only does the "roaring/humming sound" when you press the accelerator. Recently in the past two weeks it has started a what I call pulsing. Pulsing to me is it feels like a miss fire maybe and does it over and over again when pressing the accelerator ONLY. Does NOT do it in Idle. The RPMS never flunctuate as if a bad transmission may be to blame. I change my oil regualrly and keep the maintance up on my vehicle. The issue does not have any certain time it takes place as morning noon or afternoon or when its cold or warm or been driven for a long time or short time. It does not matter it does it when it wants to. However it does do it worse when traveling up a hill and speeds higher than 30 or 40mph.
There is not a hole in the muffler or any leaks on the vehicle.

I do not know what else to describe so if you have questions please politely ask. Thanks

 

[FR-425]

Yea Sorry I'm really not try'n to bust ya up.

Sounds like your AWD transfer case in having issues.
Get it to a lube shop asap to make sure it's full. probable a good idea to drain it to see if there is metal in the gear oil. If not have them refill it. and see if that quiets it down.
If it is still noisy its going to need rebuilt or replaced.

Good news is they tend to fail gradually so if you drive gently fresh lube will buy you some time to save money for the repair. Not sure the cost of the AWD type transfer case but a good guess would be $500-$800

It could also be your front or rear differential, or just a u-joint.

Best to take it to a shop you trust for some quick diagnostics.

Oh and do you have any fault codes :check engine light?

 

[devynbradley]

The check engine light isn't on but the abs and brake! Light do from time to time but always have

 

[FR-425]

Your new front tires are they exactly the same size as the rears?

the reason I ask is that on All wheel Drive models the transfer case sends power to the front and rear at all times.

The transfer case has a differential to allow for differences in wheel speed from front to rear. This differential slips when there is a difference. ( a slight differences ) caused when steering. This is normal.

However a difference in tire size from front to rear would be excessive.
Causing it to slip constantly. This would cause some noise and mess with the abs.

You cannot run different size tires on these vehicles. Same goes with running the spare. Always be sure your spare is a match.

Also don't just go by the numbers on the side of the tire actually measure them.
even the difference in size due to tread wear can cause enough size difference.

You should plan on replacing all 4 tires each time it's needed.

check with a tape measure. just measure from the ground to the top of the tire.
Compare one of the fronts to one of the rears if it is different by more than 1/4"
there's your culprit.

Your tire guy might be the dummy here. They should know better!

Good news is that for a short time driving like this shouldn't have fried your transfer.
If it has you surely have a case to sue for the repairs.

took a little time for my brain to see obvious here.

 

[FR-425]

Oh if they are a different size get the same one's for the rear ASAP!

 

[devynbradley]

Thank you sir. My husband spoke to a ford mechanic at church and I sitting at the tire dealer howgetting two tires put on the back bbecause this is the problem. I appreciate your help and confirmation that I need to do all four tires not just two BC its AWD! Thanks again

 

[FR-425]

Sure thing God bless and happy Thanks Giving.