Squeaky Steering - Belt? Tensioner? Alternator? diagnosis

[Jayzee]

Hi All

I bought a T6 2017 a few weeks back (58k miles on the clock), and it had a squeak when using the steering. I honestly thought it was jut a pully tensioner, and my friend who knows far more about engines than me also thought the same. I booked it in for a full service, and to check everything. Everything is done, but they said the squeak was the alternator and would give me the price. They've quoted £760 to replace the alternator, auxiliary pulley and tensioner.

The van drives fine, and has no other issues.

However, I cannot possibly understand how it can be the alternator when the sound is only when turning. Also, everyone who looks at it has assumed it's the belt/tensioner making the noise.

Please see the below videos I've put on YouTube.

I have bought a new battery, but not yet fitted, as the voltage is < 12v when sitting for a few days (and probably due one). To diagnose the squeaking, I've plugged my [basic] code reader in to show the voltage and the alternator is clearly charging when running. The flashing dials is just the camera on my phone.

Any thoughts? I'm going to get a second opinion, but can't get it in to another garage until next week.

Thanks in advance.

 

[Jayzee]

I have just tried WD40 on the inside of the belt and the squeak has disappeared!

 

[manfrotto]

The squeak may have been caused by the additional current draw for the power steering when turning. Does it also squeak with other electrical loads like Aircon etc.
How is the tension on the belt?

 

[Jayzee]

Other loads seem fine, but I'm guessing it is power draw. Tension is fine, and I can reach the bottom few pulleys which seem rock solid.

Now I've realised I probably shouldn't have put WD40 on it, as the squeak is back and is all the time now - I have tried a bit of water on the belt to dilute the WD40 (seems better straight away), but will have to see how it is in the morning.

I'm guessing the belt is the original, so perhaps a new belt + tensioner is called for anyway. The garage did quote for that, £380, but that price seems way too high.

 

[DXX]

@Jayzee spraying WD40 is only eliminating the symptom not the cause, if it’s WD40 petroleum based lube it’s also going to deteriorate the rubber.
The failed alternator pulley is almost certainly the cause of the tensioner wear and the belt is slipping when the additional load is applied by the power steering pump.
At the low milage you are reporting it’s highly unlikely that the alternator needs replacing, if the bearings are smooth and the output good the alternator is ok. There is a lot of extra labour to remove the alternator compare with replacing the belt, tensioner and alternator pulley.
If you have a search on the Forum you’ll find out how to test the alternator pulley clutch, also plenty of videos on youtube.

 

[Jayzee]

Thanks everyone. I'm doing a bit more reading of the forum!

 

[manfrotto]

Also check the power steering fluid level etc.
If it is only squeaking with the power steering then it could be the power steering pump that is loading up the belt (I assume on the T6 the pump is run off the same belt as the Alternator)

 

[Dundee_Kev]

I'd agree with @DXX more than likely the freewheeling pulling on the alternator