Exhaust heat shield corrosion

johnno · August 6, 2019

Had the same problem with my wife's CT (2013) last month. Heard the rattle, self-diagnosed a heat shield problem, and drove to the nearest Kwik Fit. They initially said that heat shield was a dealer only part but put it on a ramp to have a look for me. The mechanic (female) said that it was corrosion around the bolt fixing so they just refitted it with a large washer and its as good as new plus I don't need to pay anything! I offered her £5 for her trouble and the insisted that I put it in the charity box instead. Now that is the customer service that I expect (and usually get) from Lexus.

The-Acre · August 6, 2019

39 minutes ago, johnno said:

Had the same problem with my wife's CT (2013) last month. Heard the rattle, self-diagnosed a heat shield problem, and drove to the nearest Kwik Fit. They initially said that heat shield was a dealer only part but put it on a ramp to have a look for me. The mechanic (female) said that it was corrosion around the bolt fixing so they just refitted it with a large washer and its as good as new plus I don't need to pay anything! I offered her £5 for her trouble and the insisted that I put it in the charity box instead. Now that is the customer service that I expect (and usually get) from Lexus.

Lexus heat shields seem to be like their alloy wheels, not the best, but at least the large washer usually saves the day.

stormchaser · August 7, 2019

I’m yet to experience this on my 2011 at 99K. I’ll get them to have a look at it’s oil change/MOT time in October.

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Ianmorgan · August 11, 2019

I've had a similar issue withe the heat shield above my exhaust silencer box fell off and sitting on top , ive attempted to reattach and it worked for a bit but with the constant vibrations of roads and speed bumps, it has inevitably dropped again, and now my exhaust has become much louder than normal so I think I need to get this sorted properly. Any idea how much a new exhaust system will be for an '03 is200?

Greytog · August 19, 2019

My previous CT had this problem. A quick visit to Lexus Teesside and the technician who came out to look at the problem knew exactly what it was.

They took it into the workshop and 20 mins later it was fixed free of charge.

Top marks to Lexus Teesside

kamkam · August 30, 2019

We bought our CT new in 2011 and have always serviced with the same dealer (Leicester). We have the extended Lexus warrantee and found out the rear exhaust heat shield is falling off due to corrosion around the fixing bolts. We have been told that the warrantee will not cover non-mechanical faults, and does not cover the heat shield. Strange, I was told it was a 5star warrantee when they sold it to us.

royoftherovers · August 30, 2019

47 minutes ago, kamkam said:

We bought our CT new in 2011 and have always serviced with the same dealer (Leicester). We have the extended Lexus warrantee and found out the rear exhaust heat shield is falling off due to corrosion around the fixing bolts. We have been told that the warrantee will not cover non-mechanical faults, and does not cover the heat shield. Strange, I was told it was a 5star warrantee when they sold it to us.

Ask them for details of the corrosion warranty on the vehicle when it was new Kam.

Yes, the Warranty you are referring to covers only mechanical or electrical failure of a Protected Part.

Compared to 3rd party warranties the Lexus Extended Warranty is a 5 star policy, but that does not mean that it covers everything.

MadJam250 · January 13, 2020

I've been hearing a few knocking sounds on my CT lately and took it in today for investigation. Everything is fine bar the aforementioned heat shield corrosion problem. The rear can be fixed with larger washers, again as said above, but the centre section is hanging loose in the middle. £188 quoted to rectify.

I too have just extended my warranty for 2 years and looking at the documentation it states that the exhaust system is not covered. I would argue that the heat shield is not part of the exhaust system; it's a safety part/feature to shield the heat from the exhaust off the fuel tank. The exhaust system failing has nothing to do with the heat shield, it could be argued (and vice versa).

Will see what my dealer (who is excellent) says but will argue the point if it's not covered, especially too as it clearly seems that the heat shield mounting system on the CT is not fit for purpose if there are numerous examples of many corroding so easily.

royoftherovers · January 13, 2020

3 minutes ago, MadJam250 said:

I've been hearing a few knocking sounds on my CT lately and took it in today for investigation. Everything is fine bar the aforementioned heat shield corrosion problem. The rear can be fixed with larger washers, again as said above, but the centre section is hanging loose in the middle. £188 quoted to rectify.

I too have just extended my warranty for 2 years and looking at the documentation it states that the exhaust system is not covered. I would argue that the heat shield is not part of the exhaust system; it's a safety part/feature to shield the heat from the exhaust off the fuel tank. The exhaust system failing has nothing to do with the heat shield, it could be argued (and vice versa).

Will see what my dealer (who is excellent) says but will argue the point if it's not covered, especially too as it clearly seems that the heat shield mounting system on the CT is not fit for purpose if there are numerous examples of many corroding so easily.

I agree with you Martin. Please keep us all updated.

MadJam250 · February 14, 2020

Quick update. My heat shield has been affected by some damage, according to the technician, which has made the centre mounting bolt unusable. Due to this the shield is apparently not covered under warranty.

As there are still secure bolts (intact) either end of the shield attaching it to the chassis I'll probably just leave it or source a quick/easy fix to secure the centre again. The heat shield itself is fine so I'm reluctant to fork out £187 for a new one, so long as it's not an MOT failure; I'd be amazed if it was.

Ed the Ted · March 18, 2020

Guys the reason why this is happening is because Bimetallic corrosion can occur when two dissimilar metals are in 'electrical' contact and are bridged by an electrically conductive liquid i.e salt/water. The 'cell' produced can result in corrosion to one of the paired metals hence the aluminium shield rots away just like the casing on a Battery. QED

Malc · March 19, 2020

On 6/14/2017 at 4:37 PM, Malc said:

sounds like Lexus are sure " dumbing down " on quality over the years

Mine was " fixed ", after unwarranted corrosion a couple of years ago or so . welded up £30 and after about 19 years ............. the remainder of the exhaust is stainless steel and I'm told " like new "

Hey, I posted this 2.5 years ago

Well, there's another post somewhere too but can't quite find it

One of my heatshields actually parted company with it's retaining bolts sometime last year and caused a rattle on top of the exhaust but was challenging to find as it only occurred going over one particular hump in Faversham Kent ... couldn't initially decide what the rattle was

Rattle found, heat shield removed, not replaced and all is well still with Lexii ... it was just all ( 3 ? ) bolts corroded through ..... it's NOT an MOT failure for sure

Sometimes I guess they just aren't really really needed

Malc

Bowserman · April 4, 2020

Not a problem unique to Lexus.

i have had it on a Mazda and a BMW i previously owned.

Phil51 · March 20, 2023

On 6/18/2017 at 5:28 PM, pedrofromredro said:

Managed to pick up new heat sheild yesterday.borrowed some ramps as I didn't feel safe getting under the car with it being on a trolley jack as you need to get near enough the middle of the car.removed the bracket that supports the heat sheild the nut Was seized.a bit of heat and of it came.straight forward job just a bit frustrating as the heat sheild looks like it's made from the tray you cook the Christmas turkey on

Hi do you have the part number for this please

Malc1 · March 20, 2023

17 minutes ago, Phil51 said:

as the heat sheild looks like it's made from the tray you cook the Christmas turkey on

my dead and safely removed and unnecessary heatshield on the Ls400 was like a battle tank piece of steel by comparison

Malc

GMB · March 20, 2023

My 2012 IsF had the same issue and was corroded around a mounting bolt. The Lexus garage just put a bigger washer on the bolt and it was fixed. A year later and all still OK, MOT etc - all good.

A new heat shield is over £100 but extra large turkey foil from Aldi is only £3.