VTM4 Rear End Noise

[harley909]

Well I am concerned over this one.
Pulled my boat for the first time today with my 2003 Pilot. Boat and trailer weight about 2000lbs.
Have hitch and transmission cooler installed.
approx 2000km since VTM Fluid change by Dealer
got home and as I was backing boat in I could hear clunking from rear end when I turned and backed up. Thought it was the boat trailer, but nope it's coming from the rear end for sure.
unhooked and parked boat and took pilot for a ride. All ok except when I turn right it chatters from the rear end, like it's binding. Does it a we bit when turning tight left turns. No sign of fluid leak at all, the rear end is fairly warm to the touch.
Could I be lucky enough to do a vtm4 change to fix the problem?

any comments would be appreciated.

[humanoid]

It wouldn't hurt to do it again. Methinks maybe the dealer never performed the VTM service in the first place.

[harley909]

so is there a chance that a fluid change will solve the problem? I mean will the probelm go away?
I never got a vtm4 light or any warning...just the noise.

[humanoid]

It may or may not, I really can't say for sure. I'm just saying give it a try, it couldn't hurt anything, right?

[harley909]

wondering if anyone has had the rear end go in their pilot...?
what happened?

[MSTEWART]

I had this same thing happen to me in my Pilot about a month ago. I was hauling a 1500lb trailer and some wood for a deck and I noticed after a sharp right turn the rear end would clunk. I about had a heart attack when this happened. I went to the dealer and they told me to replace the VTM fluid and then do it 3 times (once a week) to flush the rear end. I changed it one time and it totally fixed the problem. I also did the tranny fluid while I was changing the VTM fluid. This is really easy to do and I'm sure that there is a post about how to do it on here.

[harley909]

ok well that's a bit of a relief.
i have changed my vtm4 fluid before but the ast time I was in a hurry so i paid the dealer to do it. i am super suspicious now that they did not do it.
i will give it a try tomorrow.

so what is with these pilots that you can't haul anything without changing the vtm4 fluid after??
seems a bit odd

[MSTEWART]

I have hauled quite a bit with mine without any problems until that happened. My Pilot has 97K and I bought it with 60K. The dealer told me that since this vehicle was a leased vehicle that it probably had never been changed. I am assuming that this is why the rear end started clunking. The dealer told me to change it every 15K to avoid any problems. A new one costs about $2,500 installed...

[harley909]

well this is an interesting story worth sharing.

i went to the honda dealer and got some VTM4 fluid and did the change. When I drove the Pilot over to get the fluid (just to warm it up before the change) I seriously had doubts that it was going to work. The rear end was shuddering and binding so bad it thought I would never make the 3 block drive there. I was absolutely brutal, worse than before I parked it yesterday.
I got home and did the change and it was obvious, water in the VTM4. It was pink and overfull because it poured out from the fill hole as soon as I opened it up, had the consistency of water.
I did the change and took it for a drive. Dramatic improvement but still binding and shuttering really bad when I pushed on the gas around any corner, left or right.
I drove back to the Honda dealer with my jug of pink fluid and showed the Service Manager. He called a mechanic who wasn't really too shocked. The Mechanic ended up going for a ride with me to see it for himself. He said he had seen this before, mainly on CRV's, but not a Pilot. He suggested I change the fluid again. I had my doubts. We went back to the Dealership and he ran off a Bulletin and told me "I am not supposed to do this but here..."
WELL WELL WELL seems this is nothing new to HONDA. It is a crystal clear problem with water getting into the rear end via the vent tube breather if the rear end gets submerged. The Mechanic suggested I follow the Repair Procedure so off I went.
I ended up changing the VTM4 fluid one more time (2 in total) and the problem went away 100%. All is well. After $80 in VTM4 fluid, a sleepless night and 3 hours of fooling around it is back to normal.
Turns out the electromagnetic rear end clutches are really really sensitive to moisture...makes them grab and not let go when there is load...I suppose a lot like when you let the VTM4 fluid go too long and it gets old or contaminated.
I am extremely thankful to the Mechanic for providing this info as I was facing a $2500 bill for a new rear end as far as I was concerned. In fact the Service Manager was working on the quote.
The problem I now have is how am I going to haul and launch my boat?
I am going to have a really good look at that vent line and see if I can add a piece of hose to it to extend it up really high into a wheelwell where it will never get submerged.
I think HONDA should make an amendment to the Owners Manual for the Pilot to advise Owners that if the rear end is going to be submerged in water (ie to launch a boat) that it is not suitable for that unless the vent line is changed or adapted.

http://i128.photobucket.com/albums/p184/harley909/Honda_III-04-05VTM4_Page_1.jpg[/IMG]]


http://i128.photobucket.com/albums/p184/harley909/Honda_III-04-05VTM4_Page_2.jpg[/IMG]]

[th10000]

WELL WELL WELL seems this is nothing new to HONDA. It is a crystal clear problem with water getting into the rear end via the vent tube breather if the rear end gets submerged.

This is nothing new to ANY manufacturer or specific to the Pilot. All clutch type limited diffs on truck based 4x4s used a "friction modifier" in the fluid to allow clutch slippage. If the fluid is not changed or gets water in it, the clutches chatter. It goes away with proper fluid. As to the water getting in this is also true of all diffs. The vent is usually not much higher than the top of the diff case and if you ever submerge your diff you should ALWAYS change the fluid in case water got in.

I had a real 4x4, '75 Frod Bronco with a 302 and limited slip diffs, and both your issues (chattering and water) applied to it as well.

[harley909]

th10000,
Well I don't see anything in the Honda Owners manual about it.
I have had a few vehicles which I used to launch my boats over the years and I have never had this type of problem before.
Why is it the Honda Mechanic has to hand this out like it is top secret anyways?

As it turns out I basically bought my Pilot to replace my Chevy truck that I used to pull my boat with. Had I of known that a 5 minute dip in the lake up to the back bumper would cause such a problem I would have thought twice about it. I did a lot of reading about the Pilot before I bought it to make sure it was suitable for what I intended to use it for. So far the whole issue of the VTM4 fluid and the required changes every 15k has been a sore point with me.
I have owned my Pilot for less than a year and have drove it for about 22,000 km and have already changed the VTM4 fluid 4 times and it probably could use a 5th...pretty expensive when you figure out.
After all that I still have to find a way to launch my boat without spending $40 to change the VTM4 fluid each time.

Thanks for the comments they were useful to me.

[humanoid]

You can do a pretty simple rear diff breather mod by extending the breather hose up to the fuel filler cap. Here's how the Tacoma guys do it.

http://www.customtacos.com/tech/index.php?article=86

http://www.ttora.com/forum/showthread.php?t=8227

[harley909]

Thank You Humanoid for the useful info.
I will be doing this mod very soon.

[th10000]

Well I don't see anything in the Honda Owners manual about it.

Harley909,

Maybe you missed the quote below in the owners manual. Yes, its not in the "towing" section, but it applies to driving in ANY water. Water above the axles can get into and damage the wheel bearings and get in the diff of ANY vehicle - thats why Honda put the warning in the manual.

No vehicle is designed to back the "lake up to the rear bumper" and I can guarantee that your Chevy had water in its diff. The only reason it didn't begin to chatter was probably that is was open and not a limited slip as I previously said.

2006 Owners Manual
Before driving through water, stop,
get out if necessary, and make sure
that:
The water is not deep enough to
cover your wheel hubs, axles, or
exhaust pipe. You could stall and
not be able to restart your engine.
The water can also damage
important vehicle components.

[harley909]

th10000,
I will have to go through my 2003 Owners Manual and look for that clause. It certainly didn't stand out to me. It does not exactly spell out the risk of ingesting water into the rear end and contaminating the VTM4 fluid like the Service Bulletin spelled out so clearly. The Bulletin that "joe public" does not have ready access to, that is.
From all accounts (my direct experience that is) the Pilot is not suitable for launching a boat if you have to go into the water up to the axles without some type of modification to the rear end vent line. Not many boats that I know of that can be launched that shallow.
I would also be concerned if I happen to run into a condition where the road was flooded enough that I had to drive with the axles submerged (which could happen actually).
If you ask me Honda should offer a kit to extend the rear end vent. It's no different that offering the transmission cooler/power steering cooler kits for towing.
In my case I will figure out a way to do it myself as I NEED to use the Pilot to launch my boat and I am not going to change the VTM4 every time I do that.
Be interesting to see what the "competition" has in their Owners Manual (Toyota Highlander/Trailerblazer/Murano/etc)