Lexus Gs300 Mk3 2005 Exhaust System

[Mateusz Debosz]

Hello !

I want to share my experience about replacing exhaust system. I've done a service on my Lex G300 2005 3.0 V6 and they found an exhaust pipe is split in place where it joints a middle muffler. They quoted a job for nearly 1200£.. because they sell this part altogether with two rear cat's. As you guess I didn't let them touch it even, especially Lexus Centre in Birmingham - their service is the worst I've ever experienced - but alright it's a different subject.

I decided to go into a stainless steel Exhaust system. I searched some info on the internet and found that many people recommend John Ashley Exhausts in Walsall. I called them and arranged a job.

I spoke to a man at their place, decided to replace a whole cat-back system and chose what tail pipe I want and how I want it to sound. I went into the most quiet system they can do, but with a hint of nice roar when I strongly accelerate.

After around 6 hours they finished the job. It looks amazing, but I can see they didn't install a middle muffler, so what's going on? John (an owner) said that according to their experience two rear boxes should be enough especially for automatic car. I do not really know what influence an auto gearbox can have on exhaust but ok. When I started an engine I said.. WOW man, it sounds gorgeous. It was late, so I said I will check it on my way back to home and let him know what I think the next day. It sounded great on idle but on the motorway it was a disaster.. it was TOO LOUD, definitely TOO LOUD. So I went back to them next week. They put a middle muffler on as well and didn't charge for job, just for a box.

Now it is AMAZING sound especially over 3'000 rpms. It is close to perfection, could be slightly quieter in range from 1800-2600 rpms but it is NOT TOO LOUD now. It is acceptable, but when I hear this roar over 3000 rpm's IT IS WORTH to have a little droning below 2600 rpm's :)

After a month I had put some sound deadening mats and liners in the boot and now is alright at lower rpm's.

To sum up, the OEM Exhaust would cost 1200£ and would give this amazing silence inside the car which is so great, but honestly V6 enignes shouldn't be so restrained. Now when I accelerate everyone around knows that it's not a common saloon, it's a real BEAST :)

Now I have a really great genuine V6 sound and amazing looking of stainless steel exhaust for as litte as 470£.

[hunslet]

I am really pleased that it worked out for you as when i tried a new exhaust system for my 2008 GS 300 it was a total failure and threw myself on the mercy of Lexus Birmingham to put it right. I won't bore you with the full story but i was fed up of having a 3 litre engine that no-one could hear. The new non-lexus exhaust sounded awful on accelaeration - more like my nan groaning as she gets out of the chair than a muscle car!

I used a company in Walsall, MIJ, for the stainless steel exhaust and have no complaints about them but it just wasn't for me. I can't remember the exact prices now but i spent about £500 at MIJ and £600 at Lexus to put it back to where i started. All i can say is caveat emptor.

[TigerFish]

I have a custom one on my GS430, love the sound

Sent from my Iphone using Lexus OC

[Mateusz Debosz]

I have read some bad opinions about MIJ thats why I did not gave them a job on my Lex. Which part of your exhaust did you replace? Whole cat back? Because Birmingham Lexus quoted me for silly 1200 quid for middle part of exhaust ( two cats and middle muffler) OEM exhaust is great for the silence it gives but could be slightly more aggresive as it should be for V6 :)

[hunslet]

Hi

Yes, i went for the whole cat back experience!

[benlamb]

Hi,

So after owning my GS300 for a month, the center silencer exit pipe has developed a terminal hole in it.

Only one option (after being quoted £955.16 +VAT for the centre section from lexus lincoln) is to have a custom stainless cat back.

How have you got on with the system after running it for a couple of months? is it that much different from the stock systems?

KR

Ben

[Mateusz Debosz]

Hi

I had exactly the same problem. If you want to keep your exhaust as stock sounding as possible do not got into whole cat back replace. Just do a middle piece which is damaged and leave rear end as it is. It will be louder anyway if they fit a free flow muffler. It is good to ask for a chambered muffler this is the best option if you want to keep your car quiet. If you want to experiance a wild beast go for a cat back system without middle muffler. With middle muffler it will be quieter but still loud.

My exhaust now is made from chambered middle muffler (the biggest they could fit), and free flow both rear end silencers.

To sum up:

- stock OEM exhaust - silence

- chambered middle muffler and two free flow on the end - silence on highway, a bit of nice roar in range of 1500-2500 rpm

- whole cat back free flow - loud system especially when driving under a load

- without middle muffler - sound like a race car and you cant hear your own thinking.

I hope it help you.

[Mateusz Debosz]

I love my car sound now it sounds like a real V6 and gives more fun. When driving under a load and gently depress the gas pedal it is very noticeable in range of 1500 - 2500 rpm. Over that the sound is brilliant. Quiet but nice roar in background.

One thing more the pipes size is also very important so the smaller pipe the quieter is system but it cant be too small because it would make gasses to flow slower and have bad influence on your engine. My pipes if I well remember are 2inch/2.25 or 2.25/2.5 inch.

[51st8]

Hi Mateusz,

Any short video how you exhaust sounds.

Thanks.

[GS3UK]

Im in the same boat , not going to bother with main dealer and just going to go down the route of SS custom made 

Anyone used Powerflow in Leicester ?

 

I really like the look of yours MD , what did it cost ?

[Baldguy]

This is a 4 year old post.... I have a powerflow system on my "new to me" Mk2 GS430 and hate it.. it drones and is being changed slightly next week to stop the droning but keep the V8 burble... if you use Powerflow just make sure they make it to your taste....

[GS3UK]

Well i have spoken to them and they have advised that it will not be loud and they can make as close to like for like to what is already on the car which is stock 

Price quoted £899 , this includes the two pipes after the cats which go to the front ***** it was also leaking from there . To do this they will have to cut the cats out and put onto new pipes 

Need to make a decision either way as i have some long distance journeys to make soon so need the car ready for that

Not much choice either way i think dealers are a no no and anything else would involve buying cats too which will bump up the costs even higher