5th Generation RX Discussion: Official Thread (RX 500h, 450h+, 350h and More)

Gecko

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Based on the early reviews of the iForce Max powertrain, I'm looking forward to "500h" 2.4T + hybrid.
 
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ssun30

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Gecko said:
Based on the early reviews of the iForce Max powertrain, I'm looking forward to "500h" 2.4T + hybrid.
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I don't know why Mag-X insists the 500h will be a single-motor hybrid.

Mag-X is even worse at predicting technical details than BestCar and their renderings are also worse. Their gen16 Crown rendering changed three times in a year. It's overall a less credible source than BestCar these days.
 
Gecko

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cookieyh said:
Most of reviews are positive, but neither fuel economy nor actual performance is very impressive.
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Fuel economy on a full size, body-on-frame truck with small-ish NiMh batteries was never going to be stellar, IMO. Lighter unibody construction and probably Li-ion batteries will make the RX 500h very different.

My comment about the iForce Max was more that I like the system and what it shows is possible. There are a lot of compromises to put that powertrain into a full size truck… but thinking about ~450hp/600lb-ft in an LS or LC “XXX”h is pretty interesting.

Plus, the driving experience of a hybrid surpasses the standard car for smoothness and NVH by far, and with more power and performance. It’s not perfect in the Tundra, but the possibilities are exciting.
 
maiaramdan

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Something wrong
I feel the RZ is already the evolution of the current RX

So are we going to see the RX share the same design as RZ but ditching the EM for ICE ?
 
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Sulu

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Gecko said:
Fuel economy on a full size, body-on-frame truck with small-ish NiMh batteries was never going to be stellar, IMO. Lighter unibody construction and probably Li-ion batteries will make the RX 500h very different.
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It seems that the objective of the P2 truck hybrid is not to increase fuel economy but to increase torque and power, and maintain payload and towing capability (bu minimizing the size of the traction battery), all without incurring a fuel economy penalty; any incremental increase in fuel economy is a bonus.

Gecko said:
Plus, the driving experience of a hybrid surpasses the standard car for smoothness and NVH by far, and with more power and performance. It’s not perfect in the Tundra, but the possibilities are exciting.
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How smooth is it? I have not driven a P2 Hybrid so I do not have that experience. So I wonder if a parallel hybrid that still uses a transmission with discrete and distinct gear ratios can be as smooth as a serial or serial-parallel hybrid (as used in Toyota cars) that does not use a traditional transmission.

ssun30 said:
I don't know why Mag-X insists the 500h will be a single-motor hybrid.

Mag-X is even worse at predicting technical details than BestCar and their renderings are also worse. Their gen16 Crown rendering changed three times in a year. It's overall a less credible source than BestCar these days.
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I was wondering about that also. Why would Toyota go to the effort and expense of developing a P2 Hybrid transaxle for use on only certain limited edition trim levels on just one product line (or maybe two if both the RX and TX share this FWD-based parallel hybrid system)?
 
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ssun30

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Sulu said:
It seems that the objective of the P2 truck hybrid is not to increase fuel economy but to increase torque and power, and maintain payload and towing capability (bu minimizing the size of the traction battery), all without incurring a fuel economy penalty; any incremental increase in fuel economy is a bonus.
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Sulu said:
How smooth is it? I have not driven a P2 Hybrid so I do not have that experience. So I wonder if a parallel hybrid that still uses a transmission with discrete and distinct gear ratios can be as smooth as a serial or serial-parallel hybrid (as used in Toyota cars) that does not use a traditional transmission.
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P2 will never be as smooth as serial or serial-parallel. You will definitely feel the clutch engaging the motor. Depending on the competence of engineering it can range from feeling like a gear shift in the best case to like a start-stop system in the worst case.

'Not tuned for fuel economy' is a convenient excuse for using a very old battery. The Tundra's battery unit was the same as the unit in RX450h which was launched in 2015. Both F-150 PowerBoost and Tundra iForce Max are somewhere between a mild hybrid and full hybrid. They both have very narrow range of fully-electric operation and very small battery for load balancing. But the F-150 is at least quite lightweight. The Tundra hybrid is very overengineered. Over 500 lbs weight penalty is unheard of on any previous Toyota hybrids, and P2 hybrids are supposed to be lighter than PS hybrids. It seems they used up all the weight savings from TNGA-F to strengthen the chassis for 800N.m of torque.

If I were a Tundra buyer I would stay away from the hybrid knowing that I'll be carrying a lot of deadweight a lot of time and the chassis is also under much more stress.
 
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qtb007

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ssun30 said:
P2 will never be as smooth as serial or serial-parallel. You will definitely feel the clutch engaging the motor. Depending on the competence of engineering it can range from feeling like a gear shift in the best case to like a start-stop system in the worst case.

'Not tuned for fuel economy' is a convenient excuse for using a very old battery. The Tundra's battery unit was the same as the unit in RX450h which was launched in 2015. Both F-150 PowerBoost and Tundra iForce Max are somewhere between a mild hybrid and full hybrid. They both have very narrow range of fully-electric operation and very small battery for load balancing. But the F-150 is at least quite lightweight. The Tundra hybrid is very overengineered. Over 500 lbs weight penalty is unheard of on any previous Toyota hybrids, and P2 hybrids are supposed to be lighter than PS hybrids. It seems they used up all the weight savings from TNGA-F to strengthen the chassis for 800N.m of torque.

If I were a Tundra buyer I would stay away from the hybrid knowing that I'll be carrying a lot of deadweight a lot of time and the chassis is also under much more stress.
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Previous Toyota hybrids replace a multi speed transmission with 2 motors and a torque split device. On AWD models, they also remove the transfer case and rear prop shaft when they add the electric motor to the rear. The additional weight for the hybrid components is offset by removing some conventional components.

For the Tundra, literally everything required to make it a hybrid adds weight. The motor sandwiched between the engine and transmission adds weight. The battery adds weight. The power transmission wires from the motor from the battery add weight. The transfer case remains. The front and rear prop shafts remain. The heavy duty differentials remain.

I'm surprised they didn't use lithium ion to keep the weight down on the Tundra, but they probably determined that the owners would prioritize the hybrid cost versus weight. IMO, the cost up of the hybrid system is thing that will prevent market penetration for the hybrid. 21mpg is pretty great for a truck that size and probably what the soccer dads will realistically get, but compared to 18 or 19mpg of the conventional, you're only saving $200-$300/yr in fuel. That $3400 is a hard cost up to swallow for such a small benefit in performance and efficiency. The entry price for a 4WD hybrid is realistically $55k. A decently optioned SR5 can be had for the mid/upper $40k range. That $60k on lot price of the hybrid is going to look like a massive jump for 50hp. They somehow delivered an expensive hybrid system only available on expensive trims that gives very moderate benefit... and they are trying to sell it to a segment of buyers that are already the most conservative.
 
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ssun30

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qtb007 said:
For the Tundra, literally everything required to make it a hybrid adds weight. The motor sandwiched between the engine and transmission adds weight. The battery adds weight. The power transmission wires from the motor from the battery add weight. The transfer case remains. The front and rear prop shafts remain. The heavy duty differentials remain.

I'm surprised they didn't use lithium ion to keep the weight down on the Tundra, but they probably determined that the owners would prioritize the hybrid cost versus weight.
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Even using a worst case scenario estimate, the hybrid components combined weigh about 150kg or less than 350lbs. Toyota's hybrid components excluding battery have among the highest power density in the industry, most of them are incredibly light. I'm very interested in how much structural strengthening they added to handle the 790N.m torque.

The 288V NiMH pack is still the largest capacity and most powerful hybrid battery they've ever made, and it has been in production for 7 years. They simply went with what they already have. Better winter performance is an extra bonus. None of their Li-ion packs in production today match its capacity, power and track record.

The truth is Toyota doesn't really have an adequate battery for truck applications. I'm hoping the upcoming LC300/LX hybrid will have better optimized batteries to fully take advantage of the hybrid system.
 
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supra93

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FLMo9y1aMAAK2ae
 
maiaramdan

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We all knew it will be a child from 2NX and current RX

But something wrong in this render
 
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