NEWRXOWNR

I just purchased a 2010 RX 350, has only 7k miles on it. Really, really nice car.

I noticed for the first time yesterday the engine ticking/knocking/rattling/whatever you want to call it sound when starting up on a cold start. It definitely goes away after about 5-10 minutes of running.

I read a few thread on this forum and others about it, and there seems to be two schools of thought.

Most people seem to accept this as "normal". They hear it, live with it, and they never have any problems. I am a new Lexus owner, so I have trouble digesting that such a luxury vehicle with so few miles would have a "normal" engine knocking sound at 7,000 miles.

A few people posted in other places that this is indeed an issue, and should not be happening. There is a a Toyota (Lexus) service bulletin that I didn't get the details on, it is LSB-0028-09. LEXUS: ENGINE TICKING NOISE AND/OR MIL ON P0014, P0015, P0024, P0025, P0017, OR P0018. ENGINE MECHANICAL. *PE

I am curious if anyone has the details on this service bulletin, and if it does indeed apply to the engine knocking sound. Also if they have had theirs "fixed".

If there is anyone that has addressed this issue, please respond, I am curious about what people's different experiences are before I go to the Lexus service department. Has any of the following helped?
- Premium gas
- High viscosity cold synthetic oil
- Dealer fixes issue
- Other fix?

Kind regards

Cruiter

Beginning with Gen III (2010 models), there is a new Lexus engine family. It's still 3.5L but it's a new low friction engine running with 0w20w oil. Also the traditional cam belts have been replaced with the timing chains such as Porsche has used for so many decades.
When it's cold, it's likely the cam chain you hear and the sound goes away as it warms just a little.

An upside is less maintenance.

Joeb427

iTrader: (1)

I had the cold start knocking in my '09 RX.Started at around 20K miles for me.
Lexus service said it was normal and wouldn't do anything about.It's not common nor very rare.
I tried using Red Line synthetic oil because it has more moly additive.It help a little bit but not enough.
A very annoying problem that's said not too cause any future engine problems.Hard to believe with that noise,isn't it?

NEWRXOWNR

I thought the same thing. I have an 08 Maxima that still drives the same (noise included) as it did when I took it off the lot. I was not expecting this kind of noise from a Lexus.

noca95

I have the same issue with my 08 RX-350, dealer said they all did it, don't think so. Noticed it at about 18000 miles or so. It does go away after about 5-8 mins., but annoying...

D

noca95

[QUOTE=noca95;6210218]I have the same issue with my 08 RX-350, dealer said they all did it, don't think so. Noticed it at about 18000 miles or so. It does go away after about 5-8 mins., but annoying...

D

NEWRXOWNR

It is strange that if it was "normal", everyone on this board would be posting it. Perhaps it is only a handful of "unlucky" ones, like the previous comment that "it isn't common, but it isn't rare".

I plan on taking it to a Lexus dealer for service and have them test it out on a cold start. I also plan on taking some video with the noise so I can show them. I guess my point is, if Lexus says that it is "normal", I want it documented on my Service Record that they actually heard the sound and the service record says the sound is normal. I don't want to be out of warranty and have the engine blow up.

I guess I'll also try and make a stink to get it fixed. But it sounds like from my research, that there isn't anything I can do, especially if the word from the Factory Trained person says it is "normal".

This is totally killing my "Lexus experience". I thought I was buying "perfection", my opinion of Lexus is totally blown with this. No way a $45,000 car should sound like this.

Cruiter

You have a new engine starting with the 2010 engine family. The timing belt is gone and has been replaced with a 'timing chain'. That fact alone will make a different and somewhat noisy (compared to previous) sound the 1st few seconds. Porsche has been using them for decades and they work well, VERY WELL. So get used to the sound of your new 'low friction' 350 engine that burns 0w20w oil.
Upside, is it will cost you less to maintain and you'll never worry whether or not you're nearing the fuzzy part in time re: can I get another 10,000 miles out of that belt if I don't change it now ??? Cause you'll never have to change it !!! On the old engine design you always ran the risk of pistons crashing into valves if you went too long and the belt broke. Now there's a big expense

Whenever there is a major modification like this one, you'll sense it in some way. This one has three ways.
1. some noise when engine is cold
2. better and more reliable
3. requires less long term maintenance .

Sorry but I read these forums and some keep complaining about the same thing even after it's been explained. Yes, the new engines make more noise (than the old ones) when cold. They will. The only fix is buy somebody Else's old technology that still has old technology belts. Enjoy the better technology here tho

Now if you truly have piston slap, that's another matter. I hope you're still under warranty

EMSLEXUSRX

My 2007 RX350 had this noise on cold start, but after it would get warmed up, it became quiet, as it should be. Drove that car for four years with no problems. Sister-in-law is driving it now.

I have to say I haven't noticed it on my 2010 RX though.

NEWRXOWNR

Cruiter,
Thank you very much for the detail. I am going to get that confirmed when I go to the dealer. I'll post a follow up once I get it back.

NEWRXOWNR

Cruiter,
So do my symptoms sound like the chain you mentioned? The sound is louder on a cold start, and certainly louder when it is cold outside and the car hasn't been driven for a day or two. It goes away after about 5 minutes of driving (it last longer than the first few seconds).

Thanks again!

Cruiter

Well I can't hear yours so... It's not a knocking sound but sort of like a sewing machine. Does that help? And yes it becomes less noticeable as the engine warms.

If that describes yours I'd not worry.

rxdan

Just bought a 2010 RX350 with 17K miles. Have the same tick tick when cold. Sounds like the diesel I used to have!!!!! It takes about 5 minutes to reduce the sound level to were the rest of the engine is louder.

I let my Rx over night and drove a 2011 RX350 loaner with 660 miles and it had the same noise but at lower sound level.

Lexus dealer service tech said it was piston slap and Lexus considers it normal unless it does not go away after the engine is at normal temp. The service writer told me it was the direct injection (which this engine does have) and th timing chain. The dealer needs to get everyone on the same story.

The service writer told me that "Your RX350 sounds like a Lexus"

I asked him what Lexus will do if it does not go away and he did not know.

I have asked Lexus Customer Service for the official Lexus position on noise and what can I expect from then if it gets worse and I am waiting for a call back.

The salesman had warmed up the car for our test drive so there was no tick. Had I heard the tick I would have walked.

Other than the tick the RX350 seems to be a good car that does most things very well.

NEWRXOWNR

Thanks Cruiter. Your description definitely sounds similar to mine.

I plan on videoing it as soon as it gets colder. I tried today, but it was raining, so the sound was largely washed out by the sound of the rain. It also wasn't cold today (50?), so the sound wasn't as pronounced.

If I get a video going, I'll post it on youtube and provide a link.

Thanks again

NEWRXOWNR

Thanks RXDan. I'll post a follow up with my results. I have a feeling it will be deemed "normal". As long as it's documented on the service records, I'm ok.

I'll definitely have to invest in a remote starter, it could be livable if I let it warm up for 3 minutes or so in the winter.