is this from standing and looking down to engine or can it only be seen by crawling under vehicle?

 

You can see it by looking down into the engine. Removing the V-bank cover (the silver one) will give you a bit better view

 

I've got 113K on my 09' GS350 and have full maintenance records from previous owner (and on MyLexus.com) and know that the water pump has never been changed. I do most of my own maintenance and every 5k miles when I'm underneath it changing the oil/filter....I look everywhere I can see for that pink residue to make sure I'm not leaking. I had the cooling system flushed and coolant replaced at 100k by the Lexus dealer and they checked and said they couldn't see any evidence that my pump is/has leaked. So....this thread always stays in the back of my mind because I'd hate to have a sudden failure that I've read about with such a pristine car. I guess I'll just keep a close eye on coolant level, etc. I've watched a few DIY water pump replacement videos on the 3GS...so...I will more than likely tackle this one myself if I start seeing the infamous "pink crust". Keeping fingers crossed!

 

If I remember correctly you can just reach into the back of the water pump pulley with your fingers and feel the pink foam.

Aisan water pumps on ebay are only about $100 bucks and takes 2 hrs to install. Its cheap insurance really!

 

Here's where the coolant residue collected on my oil filter housing:

 

it's definitely worth it. Only thing holding me back is for the 460 the labor is a lot more due to small amount of room to work up front.

 

Dang i just bought a 09 GS350 with 84k, i'm going to check this out tomorrow

 

bigblack 06, question: did you physically see any fluid leaking onto the ground? If not, how would an owner know other than monitoring the coolant level?

 

Usually a tell tale sign your pump is taking a dump, is to reach behind the water pump pulley and feel for pink foamy slime. If you have that your pump is slowly leaking and should consider replacing it soon

 

Update..

I just replaced my water pump last week, at 119K miles. Coolant levels never noticeably changed, but about a month ago I started hearing an odd noise in the front of the engine bay. It was a bit more noticeable at cold start up but seemed to go away after a few minutes. This noise became more and more prominent and it made a deep rattle/grinding noise. Had a tech friend of mine listen and he said it was probably the water pump bearing going out. Bought a new Aisin pump, Gates Idler pulley, Drive Belt and replaced them all myself...by following the DIY tutorial on this site (thanks Alchemist) and by watching a 3 part video on this on youtube. Upon pulling the old one, I did find a little pink crust on the back of the pulley wheel (which bolts onto the water pump) and pink crust on the weep hole of the old pump. Got everything back together and the engine hums like a sewing machine! No more noise. For others that DIY this fix.....I definitely recommend having a deep 10mm socket and a deep 12mm socket which are needed on least a FEW bolt heads. Also, great time to replace the idler pulley/bearing and the tensioner PULLEY (not the entire tensioner) and possibly the thermostat....because you're already there and it's not at all difficult. All are just basic ratchet off and bolt on new ones....and they're not that expensive (@ $36 for Idler pulley, same for tensioner and about $42 or so for new thermostat). For what it's worth, I NEVER saw coolant on the garage floor or anywhere else in the engine. Only found it on the back of the pump pulley and weep hole.

 

gr8fulRed, I have the same symptoms, but thought it was an exhaust leak, and the noise was going away after driving a bit. So I figured as the exhaust got hot something was expanding and closing the hole. Then instead of changing the oil myself went to Valvoline where the attendant said he added a quart of coolant. Two and Two means I need to do this. My local Mechanic is going to be $650 for just the pump and probably will put on a new belt ad replace the idler pulley and drive belt for just parts. However the procedure looks pretty straight forward. So I am very tempted to do this one. However I am very deliberate and if people on here say it takes two hours I can count on three to four hours. How long did it take you?

Thanks,

 

This job took me three hours from start to finish and that is including clean up time.

 

Add me to the list here. I bought my 2008 GS350 RWD back on 5/30/21--pretty much sight unseen. I made an offer over the phone and traveled the next day from Atlanta to Charlotte to pick it up {quickly} due to used car market conditions (going fast and going up). It IS a super nice car! Owned by a female accountant with OCD like me. No long fingernail scratches on buttons, no makeup buildup, no stains, no smoking... just nice as can be. She even left the factory film on the silver Lexus door entry sills. I did my research on the car with the VIN and full history on Lexus.com. One owner. When I met her to pick it up, there was a noise coming from the engine area, but I wasn't sure if the noise was the cam gears inside (which were replace under recall per TSIB L-SB-0157-08), or the general dieseling sound you sort of get from there. It was a bit of a rattle. I told myself that's just the way it sounds, or it was likely something I could address and drove it home.

I picked it up with just 54114 miles on it. Well, been noticing it since I got it (now just under 55.5K miles). Sometimes it would rattle, other times it would clear up, but lately a squeak was added at startup and near idle. I just finally pulled the serpentine belt off and FOR SURE the water pump is the problem - a little tug and wiggle wiggle knock knock. Plus, new to visual inspection it is slightly wet on top of the oil filter case below. All the other pulleys feel good.

13 years old, but only 54114 miles and it needs a water pump with a killer maintenance history - nothing missed or spared, dealer maintained throughout. Otherwise, the car couldn't be much better without being deemed perfect. Leather in great condition.

 

So what did you pay for the car?

 

It really does sound like you won the 3GS lottery. There are a few really good DIY videos out there to help you change that water pump for under $150 too.