Hello, looking forward to join the Lexus owners - just need to decide between the 350h vs. 450h+ on long term reliability, which is the key reason for me to pick a Lexus.

Have read in the forums and such anecdotally that the 350h is proving more reliable overall due to the relatively simpler hybrid powertrain, while the 450h+ is having repeated issues with the 12 V battery and other things that just are proving to be difficult to diagnose and fix. This article is one reviewer's long-term test, but whose experience matches what I'm seeing posted on Reddit and elsewhere - suggesting the 450h+ long term reliability is, well, unreliable, relative to the 350h.

I'm leaning towards the 450h+ due to the EV-only range, and ready to pay the higher price - but wanted to hear from owners and frequent visitors to this forum and Reddit - is the 350h a safer bet from long term reliability standpoint ?

Would appreciate any (data-driven, if possible) inputs. Thanks.

 

My take is there has to be better ways to get this information than from the very small sample of owners who post on forums like this. These forums by nature draw people who have issues or problems or concerns (this is universal from my experience over decades on many of these forums). These forums serve an invaluable service to owners. But the bias is always on the side of issues people have. It's not a reliability data set. It's useful on some levels but not a scientific data set. That would be my caution if it's how you plan to base a purchase decision.

 

I totally agree that what I'm trying is far from a scientific method, and is guaranteed to have sample bias, for exactly the reasons you mention.

The problem is, given these are new models since 2022 - what could be a better method ? There can be no consumer reports or JD Power long term reliability ratings for either of these models - which are arguably more scientific. So here I am. At the very least, I'm hoping to be polling only directly from 350h and 450h+ owners who can speak from personal experience (even if those are just point estimates and anecdotal) - rather than people speaking from hearsay.

Do you know of any other source ?

 

In that case--definitely buy a 2024 350h Premium. Mine has been perfect. For 6 months.

 

I got my car in August 2022, and it’s been nothing but great!

 

Replace 12v battery with bigger one and no more problems.

 

6 months with no problems. One recall for antenna

 

All Lexus/Toyotas are very reliable. The 450h+ has more electronics an is more complicated. m\More complication tends to be less reliable in the long run. If you are going by pure probability statistics your obvious choice is the 350h. However, both will be very reliable cars. Pick either and enjoy


YMMV,

MidCow3

 

What larger battery size fits? Have a 2024 NX 350h+ and no problems. Great car. Love the 41 mile traction battery range. Only need gasoline for trips out of town. Love the instant acceleration from the hybrid battery too. Very impressive!

 

If your 12 volt battery keeps failing , then you have a much more serious problem. Replacing the battery is only a Band-Aid fix and does not solve the problem. You Lexus dealer should do a full diagnostics on the on your car electronics and the 12 volt battery charging system. Two obvious things to look at are slow battery drain; do you have some electronic item that does not shut off and stays on when you car is parked? Does the battery problem appear after you have let the car sitting and you not driving it for a longer period of time. The other obvious are to look at is the12 volt charging system. If the charging system is not working or is not charging at an adequate rate you battery will deplete.

Replacing a battery with a bigger one, means still 12 volts but more capacity ( higher ampere hours). This is still a Band-Aid fix. The original battery is more than adequate; a larger capacity battery delays your problem showing up but does not fix it.

If you live in USA and have AAA , you can buy a battery from AAA abd they will come out and replace it and it is guaranteed for 3 years full replacement no cost. If you don't have triple AAA interstate is a very good battery ..... after you get your root problem fixed.


YMMV,
MidCow3

 

Lexus has been #1 by J D Power 23 out of the 28 years they have done their dependability survey. Consumer Reports ranks Lexus #1 in reliability. I would not be bothered with either model as far as dependability. Now as far as the 350h versus the 450h plug-in. The plug -in yes is faster. Let's look at just cost analysis of the two different vehicles. With a $15,000 difference gasoline at $3 a gallon as an average and driving 12,000 mi a year which is the national average if you never used any gasoline on the plug-in or even if you never used any electricity it would take you 16.6 years to break even.
12,000 ÷40 mpg equals 300 gallons a year x $3.00 a gallon. = $900 a year for gasoline. $15,000 ÷ $900 = 16.6 years for break even. A lot to pay for faster.

 

Though you didn't address my actual question - 350h vs. 450h+ reliability, I will digress as well and note that in Northern CA, gas is $ 5.5 a gallon. And I have excess solar production at home, which I'm sending back to the grid - and would rather charge the car with, effectively for free at home (since I get paid very little for over-produced solar power by the local power utility). The math is more in the 450h+ favor that way, aside from helping the environment and the "fast" factor, and almost noise-free cabin in EV-only mode - all of which factors matter to me.

 

I have had a 450h+ for a bit over a year now. In relation to the battery it has been flawless. I've not had any sorts of problems like that.

Generally speaking the rest of the car has been pretty fine too. No drive-train problems at all, apart from the internal combustion engine being a bit noisy and chattery when I do switch to hybrid mode (until it warms up and gets oil circulating) - likely due to it not being used for a few weeks at a time.

From what I've read, most people having problems with the 12V battery seem to be in North America/Canada. It is also not localised specifically to the 450h+. So perhaps related to the climate (extreme cold?) and/or the other common thread seems to be extra junk installed in the car by the dealers in North America, like 3rd party dash cameras or extra immobilsers/security systems, and these are perhaps causing parasitic drains on the 12V battery.

 

JD Power is not an indicator of anything. Lexus does make a great car though.

 

I have a '22 450h+ and have had absolutely no issues. I even leave my car untouched for long periods at a time when I travel. I think the posts on this forum are not indicative of the average experience and are a selection bias for people who have issues and are trying to understand if others have had the same.