Don't forget that the whole Firestone debacle with the Explorers was right around 1999/2000 IIRC also!!!

 

My Explorer never had Firestone tires. It came with Goodyears.

 

nah that's not how i roll... EVERYone who makes blanket generalizations about ANYthing is a moron

 

I saw what you did there.

 

I hope this is true. Move the Durango back to body on frame.

FCA-PSA merger plans suggest the next Durango might be a good old-fashioned body-on-frame SUV.

 

Agreed, but what is even more needed from FCA, IMO, would be a true full-sized BOF Suburban/Expedition-fighter from Dodge or Ram.....something that the Durango, tough fairly large, has never truly been.

With the D.C. Auto show coming up in just four more weeks, that's one of the things I plan to talk to the FCA people there about. Another is a possible luxury-oriented Chrysler New Yorker on the 300 platform....they retired the luxo-New Yorker nameplate a number of years ago, and concentrated on the Hemi-Sportiness for the top-line models.

With the Lacrosse gone, even with FCA's noted unreliability, I'd take a serious look at a New Yorker with the optional AWD.....no more RWD vehicles for me.

 

You could not be more right on this one, even more so now with the latest Ram's stunning interior and fantastic smooth and quiet ride. If they turned that into a 3-row full-size SUV, the "lowly" Ram brand would compete quite favorably against the upscale Denali, Escalade, and Navigator offerings.

 

The body on frame stuff you are right. I agree. Not sure how (but amazed) the Lacrosse or a New Yorker which does not exist made it to a body on frame discussion

 

Here is my perspective on this from two points of view, one being a mechanic who has driven and dealt with almost every car/truck out there from piles of 70s garbage to the newest luxury toys and fast cars.


BOF has certain advantages over unibody and if we are talking about new stuff you can buy right now they currently offer some of the safest options period in terms of crash results and strength (1500s) and die to physics will be better than any vehicle 500lb lighter and have some of the best brakes due to being required to be able to meet their tow/load ratings. The top trims also have many of the common assists and aids that luxury cars have. Ride quality has unmatched shock resistance and isolation due to the frame being separate from the body removing the "thunk thunk" noise that even the best unibody type vehicles can't eliminate. They also are a far better choice when dealing with very large vehicles since they are lighter than a same size unibody at the same strength level (ONLY when we are talking about very large vehicles) and the fact the frame is a separate item entirely allows extremely high customization ability and up-fitting.

The ride in new ones is superb, my 2017 ram rides better than my LS430 since changes in pavement (borders, lines, raised sections, uneven under each side of the vehicle) are invisible to the occupant vs the never ending noise/tone changes in my 430 when driving along the same pavement and the "thunk thunk" noise when the tires transfer from one type of surface to another. That is one serious advantage I've noticed to BOF that road irregularity is not noticeable. Shock simply doesn't transfer in the newer stuff, it is NOT a fair comparison to use a new unibody car against something like a clapped out 2002 Chevy since that would be like using a car with worn out struts vs a brand new truck. Now noise is entirely dependent on what trim/type you buy since a top trim limited with good tires is damn quiet on the DB meter vs even my 430 but a base, vinyl floored, small tire, basic shock equipped fleet spec truck is extremely loud. Same story if you swap the factory exhaust for a nice catback or long tubes, you now have background music instead of quiet, but the road shock and noise will still be very low.

Ride stability is the other big edge, unibody vehicles are kicked around by the road way more and do not have the solid "planted" feel of the large trucks that completely ignore some pavement irregularity that makes my car become unsettled and have to roll around until it's recovered. The 2018 GL is a textbook example of this, very jumpy feeling and nowhere near as easy tracking and low effort to keep where I want it vs a 2016 landcruiser. The unibody cars have sharper response that requires less lead in/anticipation when I want to perform a maneuver but in actual road holding t doesn't make any difference and it nearly allows comes down to the tires, sway bar rate, and spring rate around my usual test route. The route is in the backroads of Ohio nearby my shop that involves smooth, new pavement, then a right turn into okay pavement with some repair lines, then a decent into a bridge transition that is a 1.8 inch lip that "hits" very hard and shocks the hell out unibody cars (think about the steel plates in road work areas now hit one going 60) and provides a good test of shock damping. Then up a hill with mostly smooth road into a 4 way stop, the next turn is left onto a cinder covered older road with broken pavement that is disintegrating at the shoulders that can be taken under power to see how the car controls yaw, this old road then curves hard left and then does a hairpin hard right with potholes on the right wheels path and the left part banks up 15-20 degrees and the turn is a test of how hard I can push the car before it understeers or the rear steps out and I need to come off the power or trail brake it to keep it in line. The highest speed I can take this corner without altering the line, applying brake or throttle corrections, or coming off the power determines how hard a vehicle can turn in while the wheels are on uneven surfaces. I see no difference in body types here, it's all up to how well the individual car controls each wheel and how much mechanical grip it can generate. Some cars "feel" excellent while going through 10 mph slower than a "boat" that is able to hold, others give a very false sense of capability that snaps into a near spin without warning, and others just bring VSC back on like a hammer a do very badly.

Next bit is a pothole infested stretch that subjects both sides of be suspension to repeated impact that it has to recover from quickly or the car will need to apply brakes or will feel really horrible inside. Then a slam into a undulating single lane bridge with a big lip and totally uneven shape that will make cars torsionally flex and cheap ones creak and make noise over. Again unibody cars do not do as well in this section since they tend to get thrown around and over the bridge the front right suspension tends to send heavy shock from the lip to deep hole transition while undulating upward. Lots of head movement and upper body tossing around of the driver vs a BOF vehicle that reduces this is comparison between vehicles with similar wheelbases.

The next section is a smooth strait that you can hit 70-130 on depending on the car leading into a nice "S" turn, cars and vehicles with good sway control do very well here since the roll when transitioning out of the left turn into the right at the apex is easily managed, unibody stuff does have an advantage here since the pavement is very nice and the sharper turning response allows less effort to hit the transition perfectly and in this particular section RWD BMW cars and US RWD cars dominate whereas Audi and other AWD cars tend to plow unless I back off or trail in and bleed off some speed or precision.......but in an RS6 you can lay on the power before you are fully out of the "S" and make up for it since the AWD will pull you straight instead of spinning you out in a RWD.

From there there is a semi-gravel road that is nice to test brakes and lateral movement on, flick the wheel side to side and see how slippery the car is on the gravel and slap he brakes to see how well the ABS program works until you come to the stop sign, then turn right and you have 3/4 miles strait that starts smooth but develops undulation and some minor potholes 2/3 of the way down and then switches to new pavement nearing the stop sign. This is where I like to test higher speed stability by launching the car and seeing what it does on the imperfect section when going 80ish for slow stuff and up to 150 for fast. This bit varies hugely car to car, BOF stuff tends to just "float" over everything but some don't and react very poorly but on that same token I almost lost a S500 on the undulating part since the suspension got unsettled (entered at 105) and didn't recover and I was scared that I wouldn't be able to lower speed quickly enough for it to not come off the center line. Air suspension stuff from then on only gets up to 85 max since I didn't at all like how that car acted vs static suspension cars. Then the right hand turn allows a drift/power slide back onto mostly good road with one are with a badly done patch that again tests shock and it's back to the four way stop from earlier and back to the shop.

I've driven everything from a Rolls Royce, to a F550 through this test segment and from that I can tell you that BOF isolates the road better than even the best 7 series or S class can even if it's not as quiet and in many cases has more body roll leading to passenger head/upper body movements. Quietness is very individual vehicle dependent but I will say an S-class is awesomely nice until the entire test is ruined by a heavy shock impact going "WHAM" inside way louder than anything else experienced so far to be point it's jarring and unsettling even if up to that point the car was exceptionally quiet. On the flip side a LX470 is not quite as quiet road noise wise but the heavy impacts never made it in so the overall experience was much more pleasant. A single bad shock can ruin an otherwise great ride, the best vehicles I have driven in terms of providing a consistently good drive over this test section was a Land Rover LR3 and Range Rover with both set for max height and softest ride and a Rolls Royce Phantom, the former two were fairly quiet overall but had zero shock at all due to the air and were incredibly consistent the whole time but sucked in the turns. The Rolls was well.......a Rolls, silent, smooth, no shock whatsoever and only asked $4500 on that repair visit. Still my all time favorite in terms of serene comfort. Best driving cars are BMWs for turning control/balance under power, Audi for foolproof point and zoom, and US RWD cars for overall dynamics and speed and for FWD stuff Chevy cars actually are surprisingly good. Not great but better than one would expect from fail wheel drive, unibody "AWD" and FWD "SUVs" sucked in all aspects and honestly are trash to drive. If they weren't so convenient for the average nomies I can't imagine anyone voluntarily picking one, they don't do anything as well as a car driving wise and combine the worst aspect of cars and trucks into one sucky package. I mean they have all the roll, all the plow, no power, horrid noise, all the shock, and none of the advantages of the other two. I was laughing the whole time after driving a new at the time 2018 Ford Escape titanium due to how sad it was compared to the 2005 trailblazer I had just finished replacing the steering rack on.


My other perspective cross from working on them, most unibody "SUVs" are literally just cars that are fat, the brakes, suspension, etc are just carry over gear and the packaging is WAY worse to work on. They are so flimsy and cheaply made on average and the parts are overworked vs the cars they are based on. BOF vehicles on the other hand are very well matched to what the body is and what the roll is and generally don't have any under built sections and thus don't need to have suspension and brakes replaced like candy. Mcferson (yeah I know that's the wrong spelling) strut equipped "SUVs" are the worst offenders alongside the Mercedes GLK and GLs constantly breaking their freaking upper ball joints and wheel bearings (nightmare on the GLK) since the parts are not sized correctly. They went the path of minimal unsprung weight for the admirably high levels of steering response and feel but it's simply not a durable or strong design. I actually bought the special tools to do the job easily since I've had enough of them to make it worth it. Meanwhile in BOF land I've never had to rebuild or repair the suspension on the likes of the Tahoe (or any of its legion of platform mates), 4 runner, trailblazer, etc since the suspension is not beating itself to death and the frame is instead the one providing the strength and taking the shock vs the unibody stuff that subjects the bushings in the suspension to a lot more strain since those HAVE to absorb the blows since there are no body mount to isolate shock.

Now to step back from being a mechanic.......some background on myself and vehicles I'm used to. Both my parents are doctors (DOs) and my dad quite likes cars and is not the average consumer and my mom is one that likes a very solid/planted feel and neither of them subscribe to gimmicks or stupid features and both are good drivers with perfect records. They can buy anything they want, when it's new car time they always buy the very top model and usually keep it for a long time if they like it and the car doesn't give them problems. They tried the Mercedes top dollar SUVs and did not like the ride and reliability problems so they went full size BOF due to superior ride and comfort, on my dads most recent upgrade the cross shopping included the Ram limited, GMC Denali, Escalade, Durango SRT, Range Rover, land cruiser, F150 platinum, Toyota Tundra platinum, Audi Q7, Audi A8, and the hellcats of all types. The unibody and smaller vehicles were quickly eliminated due to the ride not being up to par with the full sizes, the car was out due to lack of space and comfort (ease of entry and cargo handling, it's a b**** to load 3gun gear in a car trunk) it came down to the Ram vs the SRT, Escalade, and Tundra and in a back to back drive the Ram won. Fuel costs are not relevant whatsoever and my dad is HAPPY to be averaging 14 mpg since in his words "the 32 gallon tank has great range so I don't have to fill up weekly" it's not about the cost, it's more about the comfort and ease of driving and "dominating" the road. The extra ability on top of those factors are just icing on the cake even if they will likely never be used. Also being in multiple deer strikes and accidents caused by other drivers and also working in an ER and dealing with paramedics (my dad is the admin of the county north of us) led him to pick BOF for safety as well from real life experience dealing with the injuries.

Personally I also love the solid and confident feel of a large BOF truck or SUV and isolation from the road that you just don't get from even the best cars. I also though recognized that unless I went with the newest stuff you can't get that in most trucks so instead of spending 70k on a new truck I decided to instead build a crazy one for fun and buy the quietest and most reliable car that I could find (the 430) to serve as my daily driver instead of my quite rough Jeep WJ since non-independent front suspension while great off-road is rough on road vs anything else. My day job is a mechanic right now (offshoot of my hobby really) so I wanted something that is effortless and relaxing to drive on the way back home and QUIET to unwind in.

The 430 has been great for this but let me tell you, I still can't get over even though this is one of the best riding vehicles and supremely quiet that a crown Vic has better road isolation. I replaced all the bushings on my 430 and it only made the road feel better instead of isolating it more lol! I wish I could combine the cabin silence and quality of the LS with the road isolation of the crown Vic to get a perfect daily but I can't so given the option I'll take the LS since the interior is nice. It's just annoying feeling and hear the pavement constantly switch with this car vs the other vehicles in my family when it's supposed to be better than them.

That's why some people straight up prefer BOF in terms of feel and driving and past that there are many more reasons it's still relevant. It's not big deal for me to pluck the body off my 2003 ram to easily access the suspension and driveline and do a full restore and upgrade, it's way harder to do the same level of work and keep a unibody long term so they are less desirable to people like me when looking past the "normal" factors people look at.

Now when dealing with smaller vehicles frames are hard to implement properly and usually you see what Honda did with the ridge line or the WJ jeeps in that the unibody steel has a very built up "frame rail" section to provide increased strength past what a car would need as applications demand. Frames are very hard to make strong below a certain weight since they require space and it's hard to adjust them to crumple if they have to conform to low weight in a small application. This means they will suck in crashes since of its made to be able to crumble it can't provide the needed strength so you end up needing to have a stronger body anyway so it's cheaper to just rely solely on the body. In large stuff like the F-150 and ram there is enough space and weight on hand that they can make the front and rear rail sections able to progressively crush very well. Not so much in small stuff.....

The point I'm trying to make is pick a vehicle based on what you want in it, what you need, and what you personally like, and that will remain in service for as long as you will need it to work for you. Depending on the type and size unibody may be better, a frame may be better, it's all up to the design overall and you can't issue a blanket statement that one is is better than another since they are built for different goals. I can argue that unibody is the cheap option designed more often than not to produced cheaply in masse with easy ability to alter the platform to market demands. Similarly BOF is the more long term friendly architecture that is in a way even more flexible since it can be up-fitted. For me personally I'm mainly a BOF guy but also appreciate a well made unibody but they are the type you kidna use and throw away once they are worn out, they are not able to be refit/restored like a framed vehicle.

 

Sounds like a typical Honda CR-V or Prius owner with little knowledge or respect.

 

I do agree that a body on frame vehicle isolates the road better. Far better

 

Agree not terribly relevant. Just one of the things I was going to bring up with FCA reps....along with the BOF suggestions. It simply amazes why FCA has not done a full-size BOF SUV based on the Ram....unless they are working on one, in secret, as we speak. The Suburban, and to a lesser extent, long-wheelbase Expedition EL, have controlled too much of that market, too long, simply for lack of competition. FCA doesn't even have a true Tahoe competitor, much less Suburban, though the Durango comes close.

 

That's more suspension and vehicle geometry related than BOF vs. Unibody related.

One of the absolute worst riding vehicles I've been in and drove many times was a 97 4Runner (brand new all season tires and healthy OEM suspension). You can feel every single bump in the road, it's extremely bouncy due to its short wheelbase and having a decent amount of un-sprung weight.

Your LX450 isn't much better in that regard, worse in some ways because of its front solid axle. Road manners are pretty horrible. But they are purpose built trucks so you put up with the poor road driving characteristics, bad handling all around, poor fuel economy, lack of interior space for its size, etc. because the trade off is one of the most capable off-road OEM build trucks ever made.

Every American pickup truck is BOF and they do NOT isolate the road better than a unibody vehicle, in any shape or form, far from it.

Your comment is pretty ignorant.

What isolates the road better is softer, taller A/S tires (which pretty much eliminates most popular A/T tire choices being D-E rated), high-articulating suspension that is valved properly for your vehicle's weight, rubber bushings in as many areas as possible, and a somewhat longer wheelbase. In contrast, stiffer tires, polyurethane bushings, stiffer body mounts, and improperly valved shocks or incorrectly spec'd springs (TOO HEAVY) will all increase road feel and carry it more into the cabin.

Most aftermarket suspension assumes you're "armored" and are built for the extra weight steel bumpers/roof rack/skid plates add to your vehicle. If you don't have the extra weight of these items and are installing aftermarket "lift kits", do not expect a great ride.

 

The suspension itself is quite stiff. 4Runners, though not as bouncy today as in the past, have never been designed for a smooth ride.

Have you sampled a Ram 1500...one designed and built in the last few years? You will be amazed at how refined, quiet, and smooth the ride is....better then many unibody SUVs. One reason is that, in addition to a lot of sound insulation, it dumps the tractional rear leaf-springs on pickups for coils.

The Honda Ridgeline also has excellent ride comfort and isolation, but it is not a traditional BOF design...it combines a unibody with a built-in ladder-frame, so you get the best of both worlds.

No arguments there.....you are correct on all counts. All else equal, tall tire-profiles do make a big difference....but vehicle-manufacturers, today, don't seem to want to use 60-series or higher on anything but trucks and off-roaders. They stick the low-profiles on most of the passenger cars to try and make them all handle like Miatas.

 

I think one of the challenges with that write up is it’s comparing a quite old LS430 to a modern expensive BOF truck. The newest LS430 is now going on 14 years old, and regardless of how well they are maintained they are not delivering the same comfort and quiet they did when they were new. They’re also quite old suspension technology, sound absorption technology, etc etc.

Make that same comparison with a new state of the art luxury sedan like say an A8, or a new S Class especially one with technology like magic body control and i think you’ll find them better.

As for BOF and large impact isolation, the reason being is you have another layer of absorption between the body and the frame. What I’ve found is that sharp hits are more damped, but they create a flexing type rebound feel that is unsettling.