Roof rack noise

[rusty]

Hi guys, I have just signed up to the forum.

Just bought and had installed the 2200mm Cheetah roof rack on the D3. It has a single wind deflector at the middle front underneath of the rack but still makes a fair bit of noise directly above the drivers head. The deflector has its downward curving lip at this point. I had heard that some people try fitting two of these deflectors to kill or at least subdue the noise. Any feedback or suggestions from anybody who has similar roofrack? Thanks

[jocurran]

My rack had 2 plates side by side as supplied and there is very little noise perhaps 1 was missed out of your package

[rusty]

Thanks for that - is the 'lip' of the plates at the back or the front?

Mine is at the back, ie right above my head, and i thought that might of contributed to the noise.

[ADMIRAL]

The lip should be at the front of the plate, but you can try moving the entire plate further back on the rack. They also have a deeper lip version, which may work better, given the roofline drops lower at the front of the D3/D4, and the rack probably acts a 'collector' for airflow blasting up over the windscreen.

The other point to check, is the length of the legs. They have a stack of different legs. You need the shortest leg they have for the back, to keep the front as low as possible to the roof line.

I have also seen a slide in rack on the front ( under the roofrack ) for a solar panel. It may actually assist in breaking up the airflow in the front section, plus be a handy spot to store the panel.

[rmp]

Just play around with different deflector positions. Deflectors can make a significant difference in the right area, and the right area is a matter of trial and error somewhat specific to each vehicle.

[Desert Traveller]

Another trick is sheet in the roofrack when it is not loaded. Generally the noise is caused by the air movement over the cross bars.

[rusty]

An update:- I got the second wind deflector installed. The supplier said two should be installed as standard! Anyway, noise is improved but still intrusive. Its quite below about 80km/hr and progressivly more noisey above that. So next step is to try loading the roof rack and see if that makes a difference. If so I will need to remove the rack when not using it. I don't mind a bit of noise if i am going on holiday but don't want it every day comuting to work.

[fender-tour]

Hi Rusty,
I am from Dolium P/L and the distributor for the these racks. I hope you don't mind me replying to you direct. (I am also a LR owner and forum user)

All D3/4 installations should have either 2 std width deflectors OR 1 extra width. We then have different depths of the lip. Because our rack baskets can be fitted to different vehicles they do not always leave the dealers with the correct deflectors for the D3/4 application. This is something we are trying to address with our dealer network and our fitment guides. (and I mean no disrespect for our dealers)

As you are in Perth, we would be happy to see your vehicle at our premises and better advise the best deflector for your vehicle.

Roof rack noise is a difficult issue and very subjective as well as being very dependent on loads, wind direction - and of course how loud you like your music! (sorry - just kidding)

Please feel welcome to contact me to arrange a visit to our Welshpool warehouse if you are still not satisfied with your installation.
Kind regards,
Adrian Stafford (08 9358 2575)

[Bushwanderer]

Hi Adrian,
It's good to see you "poke your head above the parapet". :BigThumb:

On my FR rack, I have a single deflector. How do I determine whether it is the one designed for my D3?

Best Wishes,
Peter

[fender-tour]

Hi Peter,

Thanks for the note.

It depends whether you have our 1.6m rack or our 2.2m version.

Naturally the longer the rack the greater the noise potential and on the D3/4 the front section has a greater height thus a greater air mass to funnel.

Over the time we have been refining this product for Australian use we have made changes. But the following is a general comment.

1.6m Version: A 400mm wide deflector with a 10mm lip should be OK. (Deflector is on front underside of rack with the lip to the rear - pointing down to the roof)
If you mostly travel with an empty rack and at high speed you may want to add a second deflector of same spec - and position them equally across the width.

2.2m Version: Same as above except can have a 45mm lip.

Following some feedback from our dealers, in recent times we have supplied racks with twin deflectors ex the warehouse - IF we know it is going on to a D3/4. (the same baskets can be used on other vehicles)

I am just testing the racks on my new D4 and may make a further change in deflector specs as this thing seems even quieter on the road!

Regards, Adrian (peeking over the parapet !)

[djhampson]

I think I ended up with a 1.7m or 1.8m rack because when I bought mine OL didn't have the 1.6m available. I was heading off on a trip and they sorted something out for me and gave me the rack from their demo car.

I think I've only got 1x 400mm \10mm deflector. Would you recommend the bigger lip version for this rack?

The noise isn't too bad but it could be better.

One other question for you, do you sell touch up paint for these racks? Mine's got a few scratches I'd like to clean up.

[fender-tour]

Hi,

If your rack is around 1.8m then the lip on the deflector is still going to over the high part of the roof-line - thus you can't use greater than 10mm lip.

You can fit a second 400mm wide x 10mm deflector and it will make a noticable difference - but of course you will need to remove the rack to make the change so you will have to decide if this is worth it based on how intrusive you find the noise now.

We are happy to supply a 2nd deflector FOC - to pick up from your preferred dealer. We would ship it with other goods going to the dealer so it may take a week or two to arrive.

Just let me know if you want to do this.

The finish is a satin black powder coat - use any satin black spray can paint as a touch up. Easily available from larger general auto accessory/parts outlets. Just clean it beforehand and otherwise no special treatment necessary other than a light sanding if you have gouges in the rack. THere is no issue with paint going on powder coat in this application and being aluminium there is no under-lyingcorrosion issues to worry about.

Regards, Adrian

[Bushwanderer]

Hi Adrian,
Thanks again for your input.

I have the 2.2m rack.

As the deflector is more than 10mm, I'll accept that its 45 mm. :) Time will tell whether I need two deflectors, or not. :BigThumb:

Best Wishes,
Peter

[rusty]

Adrian thanks for sticking your head (hand?) up. I would appreciate being able to come out and get you to check on the deflector installation. My (rack) lip looks like ~10mm on the 2200mm rack. I am not saying its wrong, but I would like assurance that it is either as good as it gets or there is improvement possible with changing the lip size. I will contact you after easter and work out a time. Thanks for the offer.