Underside of 4x4 is muddy, how to safely clean?

[aceofspades1]

My (fairly new to me) Range Rover P38 is rather muddy underneath and inside the wheel arches having lived in Devon for many years (amazingly, it's very solid - not rusty, just muddy.)

I've driven it about in the rain a bit but obviously the light coating of mud is fairly stuck on and won't wash off with light rain.

Any ideas on how to clean it safely? Is using a pressure washer underneath too harsh for it?

Thanks!!

[soad]

IMO Car Wash?

[A.J.M]

Pressure washer and turn the lance down a bit.

For washing the underside and arches of my Discovery 4, I just put the suspension in off road height and use the adaptor for better reach under the car.

That assumes the P38 is still on air and hasn’t been neutered with coils.

[ChocolateFrog]

Pressure washer will be fine. If it did do any damage then it indicates there was already an issue anyway.

Just turn it down a bit if you're worried.

[aceofspades1]

Thanks for the suggestions. Got it! I'll try a pressure washer and turn it down.

[Haltamer]

Chassis washer attachment - Looks like a metal bar with caster wheels on the bottom that can be connected to a quick-disconnect lance.

I've got one and it's quite effective; I think it was quite cheap on Ebay or a local detailing shop - Does the job nicely, if you have a pressure washer with a detergent mixer you can get some suds underneath too

I use mine with just a standard single extension then do a bit of peering about on my knees, there were some extensions / curved extensions but I find it easier to just get down and see what I'm actually trying to clean - Worth getting some safety squints so you don't fire debris into your eyes though!

It splits the pressure over ~4? Wide spray heads, so with my (Reasonably hefty?) nilfisk the pressure is about perfect for the application - A baby pressure washer may struggle though!

[Davie]

The lazy answer is to find some big puddles on the way home... the more involved answer is any of the above and as long as you're not blasting high pressure water at any sensitive areas, it'll be fine.

[LimaDelta]

Leave it there.

At this time of year a nice layer of mud prevents the salt getting to the chassis. There is a reason you say 'it is very solid, not rusty' in the OP. Many hard worked 4x4s don't rust because of the protective mud barrier.

[Deranged Rover]

Hammer it through Rufford Ford or similar, at high speed - that should loosen the mud!

Seriously, though, a light pressure washing will be fine. Just be careful not to spray anywhere near any electrics - it is a P38 after all, so will always be teetering on the edge of major electrical catastrophe.

[aceofspades1]

LimaDelta said:

Leave it there.

At this time of year a nice layer of mud prevents the salt getting to the chassis. There is a reason you say 'it is very solid, not rusty' in the OP. Many hard worked 4x4s don't rust because of the protective mud barrier.

That's interesting... I thought it would do harm, getting all soggy? If it doesn't do damage to have a muddy underside, I may well leave it!

[joshcowin]

aceofspades1 said:

LimaDelta said:

Leave it there.

At this time of year a nice layer of mud prevents the salt getting to the chassis. There is a reason you say 'it is very solid, not rusty' in the OP. Many hard worked 4x4s don't rust because of the protective mud barrier.

That's interesting... I thought it would do harm, getting all soggy? If it doesn't do damage to have a muddy underside, I may well leave it!

I'd also leave it. Maybe clean it off in the summer however it may have fallen off by then if we get a real cold snap?

[swisstoni]

I don’t think the ‘leave it there’ approach makes a lot of sense if this vehicle is going to be kept for a while.

In the absence of a proper chassis cleaning attachment I’ve seen people use the decking cleaner attachments inverted to fire upwards under the car.

[DickyC]

Judging by the state of the local Shell station jet wash, some folk use that - or at least use it to get the worst of it off.

[RicksAlfas]

I once read a recommendation to use a lawn sprinkler as the gentlest way of doing it.
Leave it running until the mud is so sodden that it falls off.
I have no idea if it works!

[LimaDelta]

aceofspades1 said:

LimaDelta said:

Leave it there.

At this time of year a nice layer of mud prevents the salt getting to the chassis. There is a reason you say 'it is very solid, not rusty' in the OP. Many hard worked 4x4s don't rust because of the protective mud barrier.

That's interesting... I thought it would do harm, getting all soggy? If it doesn't do damage to have a muddy underside, I may well leave it!

Mostly anecdotal, but properly used 4x4s tend to rust less than urban living ones in my experience. I never wash the bottom of them (the service techs must love me!). Steel needs O2 to oxidise, if there is a layer of mud there, it's not going to rust as fast as something exposed to the fresh air.

Think of it as natures waxoyl.

[Smint]

swisstoni said:

I don’t think the ‘leave it there’ approach makes a lot of sense if this vehicle is going to be kept for a while.

In the absence of a proper chassis cleaning attachment I’ve seen people use the decking cleaner attachments inverted to fire upwards under the car.

Brilliant, never thought of that, much obliged for the tip.

[Stick Legs]

+1 for leave it there.

I had to do some work on my Range Rover recently & the surface dirt was wet but the stuff underneath was bone dry, even having driven it to the garage in torrential rain.

I give mine a good clean at the beginning & end of summer & then it’s mostly a cosmetic rinse though the winter before next spring’s deep clean.

[Belle427]

Pressure wash will be ok but there may be nothing left of it by the time you have finished.