Comparison test of the 2015 Lexus IS 250 AWD vs IS 350 AWD reveals important differences

We look very closely at the differences and similarities between the 2014 and 2015 Lexus IS 250 AWD and IS 350 AWD sedans.

During a week-long test of the Lexus IS 350 AWD* I happened to take my personal vehicle in for service at the Lexus dealership I use. The loaner car I received was a new Lexus IS 250 AWD*. What a perfect opportunity to evaluate both vehicles back to back and compare and contrast for our readers. Let’s take a close look at the differences and similarities between these two Lexus offerings. I should also reveal my bias up front. I own a 2010 Lexus IS 350 C (convertible).

In some markets, New England for instance, Lexus only ships the all-wheel-drive version of the IS 250 to dealerships. The IS 350 is available either as AWD or rear wheel drive (RWD). However, look on any lot and the vast majority you find will have AWD. Also, on dealer lots you will almost never find any IS vehicle without the two most common option packages that add Navigation and Heated/Cooled ventilated seats. Some have more luxury options, and almost none have less. You may not want to waste too much time on the Lexus configurator trying to find that perfect match for you. As an IS owner, I suggest a trip to your local dealer (or favorite dealer) and having a chat to see what your market actually gets.

Lexus IS 250 AWD engine vs. Lexus IS 350 AWD engine
The IS 350 used to be the underdog in the market until the 2014 redesign. Then Car and Driver and separately, Road and Track evaluated the car vs. the BMW 335i, the Lexus won. Sales doubled. The reason the Lexus won is many little things and the engine was not one of the improvements. It did not need any. More powerful than the BMW engine, and very reliable, the 306 horsepower 3.5-liter V6 in the IS 350 is as much as you will ever need on public roads. More really. I have driven the IS 350 back to back with the now discontinued IS F that had a V8, and there was almost no practical difference in power.

On the road if you floor the IS 350 it surges forward so rapidly and so explosively that things begin to happen fast. Traffic comes closer at an alarming pace. You grow a wicked grin. Blue lights appear behind you. Lexus says that the IS 350 AWD can go from 0-60 MPH in just 5.7 seconds. Pretty fast, and in actual use that is about as fast as you are going to ever need to go on a road you share with children and other life forms.

The IS 250 is none of those things. Floor it and you can safely continue your phone call. Merging into traffic is not going to put your life at risk, and it certainly isn't going make you feel like you are in a sports car. Lexus says the IS 250 AWD can go from 0-60 in 8.3 seconds. Let’s make just one comparison. Honda sells an Accord with a 4-cylinder engine that can beat this car by more than a full second. The 2.5-liter V6 with 204 horsepower is refined and smooth, but it neuters this amazing sedan. We pray nightly that Lexus will discontinue the small V6 and replace it with its new 2-liter, 235 horsepower engine which has dramatically more torque. It looks like that will happen, but not this year.

Brakes and Other Differences IS 250 AWD vs. IS 350 AWD
The two Lexus IS cars handle exactly the same as long as they have the same rubber. Both of my test cars had the optional 18 inch wheels, which is what buyers are likely to find in inventory at dealers. However, they don’t stop the same. The IS 250 has smaller brakes. The rotors are 11.7 inch front and 11.4 inch rear on the IS 250. On the IS 350, they are 13.1 and 12.2 front and rear. The calipers are also different. The front calipers on the IS 350 cars are much larger and much more effective. The brake feel is noticeably different. Regardless of the actual stopping distances, the feel of the 350 brakes is much more confidence inspiring. They simply work much better.

Fuel Economy Differences Lexus IS 250 AWD vs. IS 350 AWD
Keeping in mind that the AWD system reduces the fuel economy compared to the two wheel drive versions of these sedans, the news is not that bad. In my testing, I got 25.5 MPG around town in the IS 250 AWD and about 32 MPG on the highway. In the IS 350 AWD, I got 23 MPG over about 200 miles of city and suburban driving and separately in a mix of highway and suburban driving got 27 MPG. All of these are on premium unleaded unfortunately. Much of this with the AC on.

The EPA says the IS 250 AWD is estimated to get 20/23/27 MPG city/combined/highway which is much lower than my testing. The IS 350 AWD is estimated to get 19/21/26 MPG city/combined/highway. Again, lower than I got even with the AC on most of the time. The IS 350 convertible, with its rear-wheel drive setup, but the same engine and similar transmission had returned 25.5 MPG since I have owned it over 38,000 miles. On the highway I regularly get 28 to 30 MPG. The AWD definitely reduces fuel economy.

Price Differences – Lexus IS 250 AWD vs. IS 350 AWD
The 2014* IS 350 AWD I tested had an MSRP of $50,156. The IS 250 AWD had an MSRP of $44,291. The tester IS 350 AWD I had included the Luxury and technology package which adds $1k to the price more than the equivalent IS 250 AWD I had. Therefore, the cost difference between them is about $4,865. That is a lot of money. We would like to note that Motor Trend Magazine tested the IS 350 AWD against the BMW 335ix this past year. The equivalent BMW had a price tag of $62,723. Motor Trend gave the win to BMW. I’ve driven the BMW 335ix, and I cannot imagine how they thought that car was better than the Lexus, particularly given the $12K price difference.

Summary – Which Lexus IS to Buy
Unless you are buying this Lexus to be your “winter beater,” or if you live at the top of a brutal hill that is not plowed properly, I suggest the IS 350 rear wheel drive car. Snow tires can be bought for that car for about $800 that will last four seasons. It will stop and turn better than any all-wheel drive car on all-season rubber and deliver better fuel economy at a lower MSRP. The great thing about the Lexus IS line is that there are options to suit many buyers' needs.

Related Stories:
Turbocharged engine for the Lexus IS 250 confirmed
The turbocharged Lexus IS 200t will hit BMW 328i where it hurts
2014 Lexus IS 350 and IS 250 pass Infiniti Q50 on way to number two in sales

*Author's Note: Vehicles tested were new 2014 model year cars. However, at the time of this test, the 2015 model year cars are now shipping to dealers. There are no mechanical changes from 2014 to 2015. Prices will vary slightly.

Photos by John Goreham