Importance Of Under-engine Liner?

[Maxallen123]

My under-engine liner is starting to come off... after a couple curb impacts and stuff it fell off, then fell off after another one. Today it just came off, but whereas the others had been it falling off the front bumper, this was off the back mounts, near the oil pan. I can fix it I think, just need some bigger washers to hold it on and stuff, but my question is- Is it worth it? What happens if it really goes? If necessary, should I have it replaced?

Edit: Just to be clear, I'm meaning the plastic thing on the bottom of the car. I've heard it called a drip liner too. Oh, and I just read- engine under cover.

[rvgraham]

I believe it's mostly about aerodynamics, you may lose a bit of mpg if you go without it. They didn't achieve a co-efficient of drag of 0.29 or whatever just by shaping the mirrors nicely, it's about the underside of the car as much as anything else.

Bob

[obergc]

I have the same problem with my 93 LS, several of the holes have torn through and for those fasteners, I fabricated some oversize plastic washers from an old plastic tub and it works great. I agree with Bob in that it's probably aerodynamic more than anything and you'll certainly have a different airflow around the engine without it. I personally think it's worth keeping on. It does make the oil changes a bit of a pain and I think that's how mine got damaged, by someone trying to replace the oil filter without first removing the liner attaching bolts in that area.

[UCF3]

Are you referring to the Skidpad? The purpose of the skidpad is to protect your engine from splashes from your tires, and to prevent lower engine damage from driving on differnet surfaces. not absolutely necessary, but necessary.

[FreddT]

I took that pad off a year ago. But I live in a relatively benign weather area. If I lived in Canada or the Northeast, I would leave it on, to mitigate salt spray, water infiltration, and grease build-up. And to simply keep the area cleaner than if exposed. It's hard to believe that a nearly 2 ton vehicle would get much mpg improvement with a partial underbody shield. We're not talking Nascar here.

[SW03ES]

Its not only MPG its air and road noise as well. On their own the little things Lexus throws in to curb wind noise or smooth out vibration may seem trivial, but all together they make the Lexus as quiet as it is. Lexus makes their cars so aerodynamic (the LS has had the most aerodynamic car in the world title each time it has been redesigned. First .29, then .28 with the 95 then .25 with the LS430 and now .24 with the 04.) to make them quiet, not to maximize fuel economy. The weight of all the sound deadening negates any fuel economy gained by the aerodynamics. There's probably 200lbs of sound deadening material in that car. Its so smooth and quiet in fact, that something out of place can really reduce the ride quality of the car. I'd leave it on, it was put there for a reason.

[rvgraham]

hard to believe that a nearly 2 ton vehicle would get much mpg improvement with a partial underbody shield. We're not talking Nascar here.

Actually it makes a real difference, but not several miles per gallon, just part of one or maybe one. Lexus ads from the early days made quite a fuss about it, and none of it was about preventing splashing.

[SKperformance]

It is used to channel air through the radiator at all times moving or not.

It help the efficency of the fans for cooling as well as the moving velocity of air through it.

As well as preserving the electronics like angle sensors for the engine .

[apsharp]

Wow, all that from a piece of plastic! I took mine off 60k miles ago and have not seen any decrease in mpg or increase in engine temp. Just my .02 cents

[90LS400Lexus]

My car is also missing that covering and appears it has been gone for a while. Eveything fine so-far.

[SKperformance]

sure it will work fine but so will a gm ,lol

that is what makes a lexus a lexus the overengineering of everything, besides they are a few hundred to replace them