We have had our RC 350 for 5 years now, it's been through snow and heavy rains w/ strong winds. That said, I can appreciate the car's weight through all of this especially when paired w/ quality tires and it's AWD glory. During heavy snow, I would go on the back roads that hasn't been plowed to avoid other cars and I'm in control of the car very well. Today, got caught in the middle of very heavy rain w/ visibility of just the front vehicle in the interstate and the wind strong enough that you can see waves on the road and shaking the car, but no probs with the RC.

I'm glad this car is heavy, it feels rigid and strong. The ride is comfortable due to awesome suspension. I don't care for the haters who ***** about how heavy this car is, they can go buy other cars. Hope Lexus/Toyota stays on this route.

 

You have to understand though the car is not heavy on purpose, but because of the particular development cycle Lexus was in at the time needing to produce a car with existing designs/mish -mash of other bodies-in-white (engineering term).

In other words, yes it's a safe sturdy car, but it's heavy because it's not weight optimized, not because it was a "route" Lexus has taken. Weight is the #1 enemy of car engineers everywhere. If Lexus redesigned this car from the ground up, it would be both safer + weight optimized. TNGA is extremely good at that. So no this is not the "route" Lexus intends to stay on. In fact they've already deviated from it with TNGA releases. LC, LS, ES and upcoming NX and beyond.

TNGA makes heavy use of placement-optimized 1500-grade mPa U-HS.S while relying on even further extensive use of laser screw welding and adhesives and composites. long story. The resulting TR by my estimation and reviewing of tech docs is TNGA is up in the 40k range which is exotic/race territory.

 

Heavy or not, mine does very well in our Southern weather. We don't get enough snow to matter but rain, I've
driven mine several times in rain, when you did good to see past the front of the hood. We get some "frog strangler"
downpours around here that rain just comes like a fire hose coming at you. The ole RC just takes it in stride.
This is a well built car, I've had a bunch of cars over the years as well. I'll keep mine. It's an AWD F-Sport too.

 

That is not correct.

Lexus was aiming for a higher rigidity than what was available at the time of development of the RC platform without developing something from scratch. Lexus opted not to use the full 3IS or a shortened version of the GS platform. The unibody was created from design of 3IS rear (compact /short rear end), IS-C middle (core rigidity of a convertible despite having a roof and B-pillar) and GS front end (wider front axle/longer hood for minimal V8 overhang). The base RC platform is heavy because it has higher degree of rigidity baked in than the IS and GS at the time. That is why it utilizes extra rigidity of the IS-C middle section with further integrated gussets, more rigid floor pan and enhanced apron thickness, thicker door sills etc. The RC doors are heavier than that of the IS because of the reinforcement beams in them. Lexus even claimed that the chassis was so rigid that it could have been a convertible without the need for additional reinforcements (and hence weight).

I don't want to go into details, but the RC350 is a bit heavier than the IS350 because the platform is wider and more rigid. I say a bit because the RC350 RWD and updated IS350 RWD test weights in C&D tests are around 3800 lbs. A lot of it was because the RCF was being developed at the same time (as well as the RCF GT3 racing car). In the case of RCF, Lexus further added rigidity with 10 point rear chassis brace, shock tower etc.

Also, laser screw welding was first mentioned in the development of RCF so quite possibly the base RC also uses laser screw welding.



The New Lexus RC F – Car Engineer: Learn Automotive Engineering from Auto Engineers (car-engineer.com)

 

In case anyone's wondering what TGNA is......

 

Good. They need to keep this design in terms of rigidity and sturdiness going as we plan to keep getting the RC in the future.