Is there an advantage for IRS for a full size truck that isn't applicable to other BOF use cases? Why not the mid-size trucks as well?
Genuine question. No snark intended.
Best speculation of a 2023 6th generation I have seen
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Is there an advantage for IRS for a full size truck that isn't applicable to other BOF use cases? Why not the mid-size trucks as well?
Genuine question. No snark intended.
Jetboy
New member
There are already a few IRS midsize trucks. Ridgeline, Santa Cruz, and the Ford Maverick. I think they probably all drive better than their BOF live rear axle counterparts on the highway. I'd be surprised if they didn't offer a better highway ride. Toyota's still sticking with drum brakes on its midsize truck... just sayin. Not likely they'll be a first mover. haha.
I think when they change over to electric drive, they'll all go IRS. Modular EV drive systems are almost universally built around electric transaxles and a central underbody battery pack. It's just so much cheaper to grab the ev transaxle assembly from the parts bin than using a solid axle and driveline from a chassis mounted motor. So I think it's pretty likely that they are all going to be IRS/IFS and not mechanically coupled front to rear. And the F150 Lightning is already IRS.
However, Magna has its E-beam solid axle. So it's certainly possible to keep the live axle as an EV. And it comes in 3 flavors including a twin motor with torque vectoring internal in the axle. And also the Tesla semi - it's using Model S drive units but they're build into a center section of a solid axle that then uses more traditional Class 8 truck suspension.
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2021nightshade4x4
New member
My personal take on this -
The full size trucks were the ones that stood to have their ride improved the most. We’ve all heard “it rides like a Cadillac when I’m pulling a trailer, but complete _____ when she’s empty!”
Also, Ram is putting optional air suspension in their 1500’s now, not sure about Silverado’s but Denali’s have magnetic ride, I’ve not been paying attention to Ford but I’m sure they have something nice for the Limited trims.
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T4R_Canuck
Member
We've come to a sort of weird time in the automotive world it seems, especially in North America where large SUVs and trucks dominate our driveways. A lot of people need/want a large vehicle that can haul the family camping, haul the boat to the lake on weekends, or pull their trailer, so they buy these large vehicles. The problem (if it's really a problem), is that people also expect comfort and luxury out of these vehicles. 30 years ago, if you bought a truck it was usually a 2nd vehicle, reg or extended cab, long bed pickup that was used by Dad on weekends to do chores, or go fishing, etc. Nowadays, because of the cost of a vehicle, a lot of families have trucks as their primary/only vehicle, so they want utility but also comfort for daily driving. This leads us to the introduction of independent rear suspensions, because they ride better when being driven while empty and still manage to handle the payload for home depot runs, or to tow a trailer 3 or 4 weekends a year.
Here is where my opinion changes when we start talking about the 4Runner. Call me crazy, but I think we have enough choices of crossover "SUVs" with fully independent suspensions to choose from in the world, and fewer and fewer choices of body on frame SUVs because of the changes I mentioned above. I'd personally enjoy seeing vehicles like the 4Runner, Bronco, Wrangler, etc left alone to be the solid axle, dependable off road capable vehicles they are intended to be, instead of softening them up and making vehicles like the 4Runner be just another dull crossover.
2021nightshade4x4
New member
Body on frame - I see nothing wrong with it, I like it, but once an auto magazine convinces people it’s a bad thing, it’s all over. Another thing is, look at the 2WD models, most all other midsize SUV’s are FWD based. 4Runner is longitudinal layout, gives you RWD if not 4WD.
In America, we value the smooth and soft ride of a vehicle. No consumer EVER cared about body roll until Car and Driver told us it was a bad thing. Now, unless you want to pay for active suspension - if it’s even available - rides are much firmer, and needlessly so, because all of a sudden we were then comparing our cars to a BMW 3 series. (And now, you can’t read an auto review without a plug for Tesla - no pun intended)
It’s sad how media can convince so many non-car people (and some people straddling the fence) to give up things that make their cars enjoyable. Non car people might just not be able to fully articulate what they liked or disliked about a car.
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Not really. IRS is tough to make capable and strong enough to provide proper towing power. A solid axle rear is much stronger. Also, trucks nowadays ride pretty darn amazing even with solid axles and rear interior cargo volume isn't applicable. Huge interiors with giant backseats make them pretty amazing family vehicles that can tow comfortably. Even the mid sized trucks like Tacoma, Gladiator, and Ranger need the towing power to compete, so I can't imagine they'll change either with that new generation of mini trucks out there like Maverick and that Hyundai thing.
It looks like the towing capacities of all the mid-size BOF are around 7k. The Ridgeline tops out at 5k. Would a BOF with IRS really not be able to tow 7k?
My Touareg was unibody with IRS and was rated for 7.7k, so I don't see IRS as the limitation.
The new Tundra can tow up to 12k and IIRC it has IRS.
The solid axle argument for towing seems to be an out of date argument to me - at least for light duty trucks (1.5t and lower)
Seems like off-roading and perhaps longevity are the only arguments for it in light duty vehicles.
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The new Tundra is a solid axle, as is Sequoia. I wouldn't want to tow 7k with a Ridgeline, but you're probably right. The new Tahoe went to IRS with body on frame and kept the same 8k or so towing capacity as the previous gen. Durango and Grand Cherokee are rated close to that in V8 trims, so it can be done. The big difference in all of those are big V8s vs. all of these other 4cyl and 6 cyl vehicles. There are so many other factors that go into towing numbers that are irrelevant to suspension. Tire load index, engine/trans cooling, # transmission gears, overall gearing, wheelbase, etc. I had a 2004 F250 for awhile with a 5.4 gas engine that was only rated at 7700lbs or something and it was a Dana 60/Sterling 10.25 and leaf springs all around. Same as a properly equipped Jeep Gladiator. Hell, the 4R is rated at 5k and mine sucks towing at anything above half that even with airbags (thank you 5spd AT
). Something like the F250 I wouldn't hesitate to tow more or load the crap out of it with firewood rounds, but I wouldn't want to go above that on a Ridgeline or my 4R. That's just me though. Towing #s are funny like that. Not black or white debate.Maybe I'm thinking outdated, but I still can't see an IRS setup being stronger than a solid axle. There are a lot of different attributes to strength that a solid axle wins at. The axle itself, bigger pinion/ring gear sizes, simplicity and less parts, axle shaft size and spline counts. Are there independent suspensions out there that compare? Can or would they build that and would the overall benefits of IRS warrant it? Good question. Any 1500 is towing over 10k now whereas the top IRS SUVs are peaking around 8k. I guess that brings the mid-tier class of trucks much more into picture for IRS candidates.
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thennen
New member
The people who want something like those can buy them. They're not a 4Runner, and a 4Runner isn't them. I personally don't want a vehicle like that.
RichinRidgewood
New member
You forget solid rear/front axles are cheap
I thought the Tundra had switched. Maybe that was an earlier prediction that didn’t pan out and I just didn’t update my recall.
Ridgeline is only rated for 5k - but that could just be bc it wasn’t designed holistically to tow more and not just about the irs.
Doesn’t seem like there’s a benefit for the BOF midsized to go IRS that would justify the r&d.
balong48
New member
Tundra still has a solid rear axle, but switched from leaf springs to coil springs. So the suspension did change, but the solid axle remained.
Jetboy
New member
Some recent rumor mill is that the 4R will become the Bronco/Wrangler competitor while the new LC(USA) model will basically fit the spot in the lineup of the current 4runner as a new Prado 150 successor. I had always assumed that the land cruiser name would go on a Bronco/Wrangler market entrant and the 4Runner would stick with the midsize 4door BOF wagon. But it makes sense that Toyota doesn't need a prado and a 4Runner in the same market - I know they do offer them both in some markets. But if they're re-organizing the lineup and are going to make a true Wrangler/Bronco type vehicle and a successor for the current 4Runner as midsize BOF wagon, I'm not sure it's very obvious to me which nameplate goes on each one. I hadn't really considered that they could go with the new LC(USA) as a 4runner replacement and then build a new Wrangler/Bronco under the 4Runner nameplate. But I can't really make a strong argument for either one over the other. I tend to think only Land Cruiser has the heritage to rely on for a short wheelbase model that would garner the same press and image as the Wrangler or Bronco.
However, I also don't think it matters. If Toyota built a BOF SUV with a removeable top (or not) that came on 37's with front and rear lockers, optional winch, armor, and 12+ inches of suspension travel for $45k, they could call it the Toyota Turdmobile and it would sell as fast as they could build it. Call it a 4Runner and that's cool too.
However, I also don't think it matters. If Toyota built a BOF SUV with a removeable top (or not) that came on 37's with front and rear lockers, optional winch, armor, and 12+ inches of suspension travel for $45k, they could call it the Toyota Turdmobile and it would sell as fast as they could build it. Call it a 4Runner and that's cool too.
TexasFunRunner
New member
Interesting, do you have a source, perhaps a link at 4r******.com?
[MENTION=166416]Carmaker1[/MENTION], have you heard anything about this?
Agreed, to me, the only sensible nameplate to go on a Bronco/Wrangler competitor is Land Cruiser, but maybe I'm showing my age.
Blackwatch
New member
I'm not sure if automotive press is where he is getting this rumour but he did mention this in this latest video. The 4Runner was sent back to the drawing board after Toyota saw how well the Bronco and Jeep were selling. He believes they are going to change the 4R to compete against the Bronco.
NEW PREDICTIONS FOR 2024 TOYOTA LAND CRUISER, 2024 LEXUS GX & 2025 TOYOTA 4RUNNER - YouTube
Jetboy
New member
That is what I was referring to. It seems to fit the missing pieces for me as far as how you could have GX and LC model that are the same vehicle that fit between 4R and Sequoia and not end up with roughly identically sized and segmented vehicles. The 4R and GX already near-twin models. Adding a third Toyota branded GX sister vehicle just doesn't make sense. It would be like GM selling a Tahoe and Yukon. Wait a minute... anyway, if you move the 4R to be a more hardcore off-road model then you have a lineup that fits together really nicely. And there's really no need for the LC300 because the Sequoia and new LC(USA) model bracket the LC300 with the sequoia effectively a bigger more powerful version and the new LC(USA) being a similar sized more off-road dedicated wagon.
The only missing link is a removeable third row non-hybrid Sequoia for people who actually want to have a larger SUV with room in the back to haul stuff. And I'm still unclear on how the GX would differentiate from the LX600 if the GX has the same powertrain, same size, and a 3rd row.
TexasFunRunner
New member
Thanks for confirmation of the source, I take AP David with a huge grain of salt, if he has any truth in his speculation it gets lost in his click bait approach.
Regarding Sequoia, I here people arguing over the merits of a two door vs a four door Jeep or Bronco but never over the merits of going larger. To me, anyone thinking they need larger are in a different ballpark, Grand Cherokee, Tahoe or Suburban for Overlanding, etc.
TexasFunRunner
New member
I just forced myself to watch David's latest speculation video, he did not say anything we have not discussed on this forum in the last few months.
Username = Jetboy, as in someone who Jets off to Japan. :gossip:
[MENTION=118321]Jetboy[/MENTION], fess-up, the you AP David incognito?
Username = Jetboy, as in someone who Jets off to Japan. :gossip:
[MENTION=118321]Jetboy[/MENTION], fess-up, the you AP David incognito?
Jetboy
New member
Hahaha. I'm a middle age white guy. I don't have any special inside info. I sure as hell don't understand Toyota's marketing decisions. I'm just bored and daydreaming because I'm stuck in Alaska for a year or two.
I have been to a couple of Toyota's factories and facilities in Japan. But I'm no insider at all. I work in aviation. My closest insider is a friend who owns a Toyota dealership. And they don't know anything we don't.
I don't put much faith in AP David. Carmaker1 is effectively the only source of early info I've ever seen that's consistently reliable. Everything else is just imagination.
I thought this was an interesting question that he raised. The idea of the 4R becoming the new heritage 4x4 model never really crossed my mind before. The 5th gen is the most popular gen ever. So it doesn't really make sense to completely turn that upside down and replace with an LC nameplate during the peak of popularity. But it still oddly kinda fits in it's own way.
TexasFunRunner
New member
I think we can all agree, AP David is reading this forum and using it as a partial source for his videos.
"Stuck" and bored in one of the most beautiful states in the US, you need to recalibrate your expectations and adventures.
