As I was driving along the other day, the black, plastic shield came off the underside of the front of my car. I'm looking to get a replacement, but I don't know what it's called, or even if it has a name. Any ideas much appreciated.

 

If you are looking for the front bumper undertray for an X300, the JLR part number is: BEC19939. There is also a fitting kit: BEC19939KIT.

Both are most likely available from a local Jaguar agency, or from SNG Barratt.

 

Perfect! Thank you very much.

 

Another quick question on this subject. Will driving the car without the undertray cause any issues?

 

The undertray was missing off my car when I bought it. It still is missing...

You will loose a bit of aerodynamic efficiency, and possibly gain a little noise. Otherwise it will be ok.

 

The undertray is also known as the splash shield/guard, so drive without one at your own risk. A new one will set you back by about GBP108, but you should be able to find a good, used one cheap from the breakers, but make sure you get the shield retainer screws or clips ("the installation kit") as well, because your loss of the undertray was largely due to some retainer screws missing or broken.

 

This is what was concerning me. As it's my everyday car, will driving it on wet, salted roads without an undertray just be storing up corrosion problems for the future?

 

Yes.

The undertray protects to a large degree, the underside of the radiator and condenser, both rust-prone areas. It will protect them from damage even if it has to sacrifice itself. It also helps protect wiring harnesses and connectors from water and dirt.

Uro Parts makes a replacement. It is available at Rock Auto for $58 plus shipping. They are all over ebay too. I had to replace mine and this Uro Parts fit very well. I bought the pin kit some time prior, on ebay I believe. StuII, this should be available on ebay UK.

The greatest danger to your undertray is the USA 4-inch parking block. They will tear out your undertray if you pull up onto it, particularly when you try to get off of it. The undertray has a lip going across it that is at exactly the wrong height. For this reason, I sawed that lip off of my new one, and now when I pull in too far, the front end glides right up the parking block and right back down when I back up, with only a few added scratches!

It seems like the undertray is a consumable part on this car. Many of us have been, or are now driving around uncovered down there! Good that Uro makes a pretty inexpensive replacement.

http://www.rockauto.com/en/catalog/j...ash+shield,358

 

The main reason for the undertray is cooling. It deflects the air so as to create a partial vacuum in the engine bay and assists with pulling air through the radiator at speed.

Assuming the rest of the cooling system is up to scratch, it shouldn't be a major problem driving without it. Mine decided to self destruct on the highway at about 80 MPH. Made quite the noise as the wind tore it off and it broke up under the car.

 

I've ordered a new one and the fixing kit. Mine came off when I was doing about 70mph. It was quite a relief to find that all that noise wasn't something catastrophic!