E-450 with V10 serpentine belt instability and noise

[Bullitt6283 0]

I have a 2016 Jayco Class-C motorhome built on the E450 cutaway chassis with the V10 motor.

I've been chasing a noise for a long time, as have been many other 2011-2019 E450 (cutaway) motorhome owners with the V10 motor. It sounds like spark knock, but better fuel does not help at all. There is a history of owners taking their vehicles into the dealer for a diagnosis, but the problem remains unresolved even after belt/pulley/tensioner replacement.

One of the owners on the Jayco website found the issue.

 

VIDEO:  https://youtu.be/Oa6cr2dFkPE

 

--> As it turns out, there is serpentine belt instability on these motors. <--

Further, it was discovered that prior to 1999 there used to be an additional idler pulley mounted between the PS pump and alternator, the area where the belt is fluttering.

The threaded mounting boss still exists.

Why was this pulley deleted???

Can I safely put one back on???

 

 

Edited January 6, 2021 by Bullitt6283
corrected

[twintornados 2,844]

I would say order the pulley and install it....should help with your issue.

[Bullitt6283 0]

1 hour ago, twintornados said:

I would say order the pulley and install it....should help with your issue.

 

That is my intention.

I am wondering, however, if there could be a reason why the pulley was omitted on recent motors.

Was there an issue, or was it purely a cost-reduction.

 

.

Edited January 5, 2021 by Bullitt6283

[Gidyupgo 3]

Following

[Bullitt6283 0]

In order to gain engineering insight into the belt noise and  'omitted pulley' subject, I contacted Ford Help  and the Ford Performance Techline. I also contacted the Motorhome Customer Assistance Center. 

None of these sources could help me.

 

.

[twintornados 2,844]

4 hours ago, Bullitt6283 said:

In order to gain engineering insight into the belt noise and  'omitted pulley' subject, I contacted Ford Help  and the Ford Performance Techline. I also contacted the Motorhome Customer Assistance Center. 

None of these sources could help me.

 

Who needs engineering insight when you have the proof you need under your hood? Put the pulley in and and let us know how it works.

[Bullitt6283 0]

3 hours ago, twintornados said:

 

Who needs engineering insight when you have the proof you need under your hood? ..........

 

Glad you asked...

1. The UBS (unstable belt syndrome) has evidently existed undiscovered for some time. The UBS noise sounds a lot like spark knock and most owners thought that is what it was. Many motorhome owners have tried to diagnose the UBS noise issue themselves, or have taken their RVs to Ford Service who were unable to solve the real root cause. These motorhome owners are a conservative bunch, and would prefer a formal pronouncement from Ford that adding the idler pulley is an appropriate course of action.

2.  I play with a highly modified Ford Mustang Bullitt, and I am very familiar with the "Law of Unintended Consequences".  This Law becomes troublesome when a car is modified for a good reason, but the modification causes an unforeseen issue which can be worse than the original problem. So, for my motorhome, which I hope continues to be very reliable, I am concerned that adding the idler pulley may cause another problem. After all, the pulley had previously existed, and then it was removed. Why??

 

Cheers,

Ron

.

Edited January 7, 2021 by Bullitt6283

[twintornados 2,844]

18 hours ago, Bullitt6283 said:

I am concerned that adding the idler pulley may cause another problem. After all, the pulley had previously existed, and then it was removed. Why??

 

The pulley in question is under $10 at any parts store, the reason why is obvious..."cost of part + amount of engines produced" is a number that can be eliminated with little to no concern from the average consumer. You are not average. My guess is, you will not get a satisfactory answer from them so go down to the parts store, drop a little coin, put it on and let us know how it all turned out. Welcome to "Hot Rod 101".

[Bullitt6283 0]

6 minutes ago, twintornados said:

 

...Welcome to "Hot Rod 101".

 

I did a bit more investigation....

According to the RockAuto listings, Ford went from a wider 8-rib belt for 2001 and earlier V10s, to a 6-rib belt in 2002 and up.
This may help explain why the second idler pulley disappeared in about the same time frame.

 

 

Edited January 8, 2021 by Bullitt6283

[twintornados 2,844]

3 minutes ago, Bullitt6283 said:

I did a bit more investigation....

According to the RockAuto listings, Ford went from a wider 8-rib belt for 2001 and earlier V10s, to a 6-rib belt in 2002 and up.
This may help explain why the second idler pulley disappeared in about the same time frame.

 

Since the idler pulley in question rides on the top of the belt and not on the ribbed side, it should be just fine. Ford going from an 8-rib to 6-rib design proves my point, saving $$$. You may also see that the 5.4L Triton probably uses the same belt too, further cutting costs.

[Gidyupgo 3]

Bullitt6283, I am surprised more people aren't discussing this. Maybe on a different forum? Anyway, 2016 6.8 in a Class C with 41k miles. It's been making this noise since new (4 years) at 2100 rpm. Installed the driver's side idler today. Pulled the air filter for access and easily deflected the belt enough to install. I did not loosen or replace the belt. Inspected it and it looked fine. Leaving tomorrow for a 750 mile trip. 

[Gidyupgo 3]

Just to follow up. Rattle noise  at 2100 rpm is gone. No problems.

[twintornados 2,844]

8 hours ago, Gidyupgo said:

Just to follow up. Rattle noise  at 2100 rpm is gone. No problems.

Nice...glad you "got" it...

[Bullitt6283 0]

9 hours ago, Gidyupgo said:

Just to follow up. Rattle noise  at 2100 rpm is gone. No problems.

Great News

 

Cheers!

[Gidyupgo 3]

Again, as follow-up. 9000 miles since the idler was added on the driver side. No noise and no other issues. 

[Hubcap 0]

Need the part number for the bolt that holds it on. I assume just order the pulley for a pre 99? Thanks, 

[Bullitt6283 0]

9 hours ago, Hubcap said:

Need the part number for the bolt that holds it on. I assume just order the pulley for a pre 99? Thanks, 

.

 

Does your engine have a 6-rib belt or a 8-rib belt? Somewhere around the 1999 timeframe there was a change.

Later models have the 6 rib belt.

My vehicle is a 2016  Ford E450 chassis and the V10 gas motor and the 6 rib serpentine belt.
The bolt I used is  p/n N808102 S437
Pulley is (Motorcraft YS-385) #1L2Z-8678-AD.

 

.

Edited November 4, 2021 by Bullitt6283

[chromeronzo 0]

     I guess I'm a little late getting here, but I'm glade that I found this forum. Thanks to all...I just joined this conversation, and do I have a little story that will really fire you up.
     I have a 2015 E-450 Class C Winnie..6.8L V-10(I love it with the SCT upgrade)...with 48,000 miles. Great running motor home. Just recently started having this same noise 500 miles ago, and rather than sit for days to get it repaired, I soldiered ahead and drove home. Took it to my local Ford Dealership...spoke to the service writer(very helpful) and let him take it from there.

     Now, I have been working on cars since I was eleven. I know the front from the rear, I also have 2 vws, and can pretty much do all of my own maintenance. In fact, I earned a living from bending wrenches for quite awhile(just do not like all of the electronics); but, when I heard after paying $285.00 for an RV diagnosis, I was stunned. What they found out is that I had a noisy valve cover! Yep, those darn valve covers can sure get noisy. Whatcha goin' to do. Replace the valve cover. Apparently, the oil filler opening came loose? from the inside of the cover--spot welded I guess...could not really tell from the diagram presented to me. So while they did open-heart surgery, I had the dealership replace the serpentine belt.

     So here we are...$1200.00 later(all but $478 paid for by Good Sam extended warranty), and I'm not sure if the sound has dissipated. From the Ford dealer to the RV shop for some needed maintenance, and when I pick it up from there, I'll give it a good going over--noise and missing pulley.

     It sounds like the FIX in this forum could and should make me smile...thanks again...I'll update later in the year.

    

  

 

 

[chromeronzo 0]

Thanks to Bullit6283---ordered my parts today--double checked on your numbers---spot on. Will receive them on Monday...go in on Tuesday.

[GDaddyBRT 0]

We have a 2017 V10 powered RV, Fleetwood Jamboree 31U. Love the RV but the belt noise has been driving us crazy. The sweet spot in RPM is about 2100 up to 2500 and of course, 2100 is where the noise starts including every upshift to get to cruising speed. We put the idler wheel on and just like magic, the noise is completely gone! After several years of listening to that crap, I still anticipate hearing  it but it is just psychosomatic it doesn't exist in the real world anymore LOL. If you are having these issues with noise driving you batty, put the idler wheel on and enjoy your new found peace and quiet. Have a great day!