2006 AWD - Grinding noise from rear

[Beaullieu]

I've got a 2006 AWD automatic with 18,000 miles. I've just started noticing a slignt grinding noise coming from the right rear of the vehicle when making a sharp left turn. It's particularly noticeable when parking or otherwise moving very slow and to some extent, you can almost feel the grinding coming through the body of the car. When turning right, everything is normal.

I've not yet taken it to a dealer but plan to do so next week. Has anyone had a similar experience or have any idea what may be going on?

[2RedV's]

I've got a 2006 AWD automatic with 18,000 miles. I've just started noticing a slignt grinding noise coming from the right rear of the vehicle when making a sharp left turn. It's particularly noticeable when parking or otherwise moving very slow and to some extent, you can almost feel the grinding coming through the body of the car. When turning right, everything is normal.

I've not yet taken it to a dealer but plan to do so next week. Has anyone had a similar experience or have any idea what may be going on?

You are kidding, right? ;)

You need to start reading the forums more!

This is the CLASSIC SYMPTOM of the rear differential fluid being worn out.
The dealer should cover it under warranty for you. If they balk, call Honda Corporate and open a case. The manual (it is wrong) states that the fluid should last 90,000 miles. Since it doesn't - you should get it done for free. A dealer near me charges about $40 for a rear differential fluid change.

Most people are changing the fluid around every 30k miles. It is quite simple as a DIY job as well, but you must ONLY use the official Honda Dual Pump fluid. It is a special formulation hydraulic fluid. It is not auto transmission fluid or gear oil as in some other brands of rear differentials. It cost about $6 a quart at the dealer. You will need about 1.2 to 1.3 quarts so if you are going to DIY, buy 3 - then you have enough to do 2 fluid changes.

[Beaullieu]

2RedV's

I guess I have been a little slack in reading the forums lately....:D

I suspected either a diff fluid or bearing issue starting and I really appreciate your confirming the fluid as being the likely culprit. I'll get it to the dealer asap and make sure they cover under warranty.

Do you happen to know if I'll cause any damage if I put a couple hundred more miles on it before I get it to the dealer (need to go out of town in the morning)

Thanks much

[2RedV's]

2RedV's

I guess I have been a little slack in reading the forums lately....:D

I suspected either a diff fluid or bearing issue starting and I really appreciate your confirming the fluid as being the likely culprit. I'll get it to the dealer asap and make sure they cover under warranty.

Do you happen to know if I'll cause any damage if I put a couple hundred more miles on it before I get it to the dealer (need to go out of town in the morning)

Thanks much

Tough call..

You see, when you are hearing noise it is because the fluid is already worn out and the clutch pack is rubbing against itself because the friction reducing properties of the fluid are gone. Soooo, yes, you are causing "damage" but since so many people drive for months before they bother to get it fixed, I would say you are OK. Still, drive it easy and avoid especially sharp turns.

It really is an amazingly resilient piece of engineering.

[Beaullieu]

I set up an appt with my dealer (Ed Voyles Honda - Marietta, GA) this morning to check out the reaf diff fluid and grinding noise. The service advisor confirmed the grinding noise is most likely fluid breakdown as you suggested.

However, when I brought up covering this under warranty, he balked and said they recommend a 15k service interval and do not cover rear diff fluid under warranty even though the owners manual recommends a 90k service interval. I pressed the issue a bit and the service advisor conferenced in the service manager who offered to change the fluid no-charge this time as "good will" since I bought the car there but future fluid changes would be on my dime.

This dealer charges $69.95 for changing the diff fluid. I can assure you that I'll change it myself going forward...

[2RedV's]

Good job! Maybe you should ask them for that 15,000 mile service suggestion in writing and then forward it to Honda, asking for it to be free for you every 15,000 miles.

[Deltantony]

I really is the Double pump oil.
I had the same problem to.
Bought three liters from the original Honda Dual Pump Fluid,
the mechanic told me not just to fill it but do a,..hm..how do you call this in English, flooding, (what you do after you have brusched your teeth):D
He told me that the thing that causes the problem is that at flatlands (like the Netherlands were i life) you will not use the 4 wheel-drive -mode enough, then the oil starts collecting water because of condensation. And in combination of the wear-dirt collected from within the diff, this makes the noise.

In detail this worked for me:

Find a tool to open the bottom screw, has to be a square 9,5 millimeter thing, then let go of the oil, looks clean! but isn't, of else you wouldn't hear the terrible noise from the back. Put in the screw again and open the top screw. Fill up with the whole one liter (don't know how much it is in gallons or quarts??) and then close up the screw again. Drive for about 10 minutes and be shure to turn a few very tight circles. That makes the diff work.
I did some really terrain work, mull sand and lots of power.
Than after comming home again, let the new oil go and fill het op again with another bottle. For me this was more then enough.
I now have another liter which i will use for one more flooding. That sdhould be enough for the next 30.000-40.000 miles.

Good luck.

Deltantony

[2RedV's]

The mechanic didn't quite know what he was talking about...

The fluid is hydraulic and is constantly being pumped back and forth thru the system. There are 2 pumps within the rear differential. Notice that it is called Dual Pump Fluid. Being worn out has nothing to do with how flat the land is.