Hello Everyone,

First of all, a sincere thank you for reading my post & for any provided help/insight in advance. I have a 2009 XKR portfolio series and it was driving as smooth as butter until this morning. The moment I went to back out of my driveway and shifted gears into reverse, I heard this horrific loud rambling noise. Seems like it could possibly be coming from the front because it starts to make a rattle & shake a bit. Any leads as to what it may be?

Much Appreciated,

Chanel

 

Obviously engine rather than drive train. If you open the bonnet and listen you will have a much better idea of where it is coming from but it could well be one of the drive belt pulleys / tensioners or one of the devices driven by the belt like the water pump /alternator / steering pump / supercharger etc.

Richard

 

I've removed your duplicate post of this question in General Tech Help. Please don't multiple post the same question across forums.

That's a very short video but it could be a collapsed cat. They have a sound like shaking pebbles in a tin can when they break up internally.

Graham

 

Hello,

My apologies, I’m new to posting and didn’t notice the first one actually did post. The video was cut short because it exceeded the maximum. What does a collapsed cat mean? (It’s the first time I’m hearing this term). Many Thanks!

 

The Catalytic Converter has a ceramic honeycomb coated with precious metals. The honeycomb can shatter with even low impact. This is what it looks like cut open:





An increasing problem here in the UK is theft. The honeycomb is coated with precious metals worth a lot of money as scrap.

Graham

 

If its only in reverse, Id listen to the transmission using a mic set up and if its the tranny, start with a fluid change. You dont have to replace the pan for this. Have a shop simply drain and fill. Its less fluid compared to dropping the pan but its plenty enough to be able to fill with some fresh fluid at the correct level. I replaced the pan, and mechatronic 3 yrs ago, then this year, it developed a 3 second delay going from D to R. In a rush, I would gas it and the transmission would kinda slam into R. I had a few liters of fluid replaced, and suddenly the thing is nice and crisp. So try that first. But Im sure its not the transmission from your description. Its probably the belt tensioner, a cat, or heat shield. Cars act different when in reverse. Geometry and frequencies change when going in the opposite way of the usual.

 

Thank you so very much for all the help & tips! Turns out, it was a collapsed motor mount that needed to be replaced and apparently when it is shifted into reverse makes the loudest sound alive. I love this community, I can always count on knowledge and help. Thanks to each of you!

 

Thanks for posting the outcome. Too many ask a question then forget to do this.

Graham

 

If it's in reverse it's left side (drivers side ) I did a write up on this as rack needs to be released....also good news is xf,xj,s-type mounts will fit for along time we thought the xk motor mounts would only fit which are very pricey

C2p17845 I used these recently