Convertible Exemption and the Wrangler Removable Roof

[94grt]

I see a lot of banter about the JL moving away from a fully removable roof and very few discussing the REAL reason behind such a potential change.

It's not about costs, design challenges or any of that, at least not in any majorly impactful way to cause such a big shift in Wrangler design. This is about the NHTSA convertible exemption that the Wrangler has benefited from up until now, but which the NHTSA is potentially looking to overturn.

The FMVSS 216 exemption allows vehicles classified as open-top / convertibles to use an alternate crash test and less stringent requirements in which it has to resist less force than other vehicles. The fear is that the ever restrictive safety mandates will cause the NHTSA to get rid of the exemption and require extra strength in the A pillar of the JL Wrangler. FCA has no plans to shorten the life cycle of the next Wrangler so the threat of a law change out into the future must be assumed and seriously considered. I believe they have designed the JL with the worst case scenario in mind.

This doesn't have to mean the death of open air design altogether but major structural and design changes need to be made to the roof. An open fixed structure and a fixed non-folding A pillar with higher crush loads more in line with a conventional hardtop and "soften the blow" literally with retractable opening roof panels (cloth and glass) could be the ultimate solution.

Based on the educated speculation I believe we'll see exactly this change in the JL Wrangler.

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[Campbell]

Thx for that... learn something new everyday! Think I read here that there's likely to be a roof substructure on the new model underneath the new tops (glass and/or retractable soft top), which would be in line with what you're predicting.

Wonder if the JL body life cycle is planned to be 10 years like the JK.

 

[Biker Dan]

Wait.. So all convertibles going forward would have to meet the same requirements? There's a ton of verts out there, wouldn't ALL of them have to prepare for this type of rule change or is the Wrangler unique in some way?

 

[94grt]

Wait.. So all convertibles going forward would have to meet the same requirements? There's a ton of verts out there, wouldn't ALL of them have to prepare for this type of rule change or is the Wrangler unique in some way?

Maybe I should have been more clear. There is an exemption for all vehicles classified as convertibles (officially that means vehicles whose A pillars are not joined with the B pillars or rearmost pillars). They are exempt from the stricter requirements of FMVSS No. 216 (Roof Crush Resistance). This is unlikely to change anytime soon.

As you know the Wrangler has a rigid structural member that connects the A and B pillars so it does not fall into this definition of convertibles. However, in a previous rulemaking the NHTSA stated that "open-body type vehicles" are a subset of convertibles because it has a removable compartment top and therefore excluded it from the Roof Crush Resistance standard which requires roof crush protection over the front seat area even though it does not fall into the definition of convertibles.

The proposal is to limit the exclusion only to vehicles that fit the definition of convertibles and not "open-body type vehicles" such as the Jeep Wrangler. The NHTSA has stated that it believes open body type vehicles are capable of offering roof crush protection over the front seat area due mainly to the fact that it has a fixed structure connecting the A and B pillars.

If this change is made, it will have a big impact on how future Wranglers are designed and built which is why I believe we're going to hear a lot about changes to the JL roof.

 

[Biker Dan]

Maybe I should have been more clear. There is an exemption for all vehicles classified as convertibles (officially that means vehicles whose A pillars are not joined with the B pillars or rearmost pillars). They are exempt from the stricter requirements of FMVSS No. 216 (Roof Crush Resistance). This is unlikely to change anytime soon.

As you know the Wrangler has a rigid structural member that connects the A and B pillars so it does not fall into this definition of convertibles. However, in a previous rulemaking the NHTSA stated that "open-body type vehicles" are a subset of convertibles because it has a removable compartment top and therefore excluded it from the Roof Crush Resistance standard which requires roof crush protection over the front seat area even though it does not fall into the definition of convertibles.

The proposal is to limit the exclusion only to vehicles that fit the definition of convertibles and not "open-body type vehicles" such as the Jeep Wrangler. The NHTSA has stated that it believes open body type vehicles are capable of offering roof crush protection over the front seat area due mainly to the fact that it has a fixed structure connecting the A and B pillars.

If this change is made, it will have a big impact on how future Wranglers are designed and built which is why I believe we're going to hear a lot about changes to the JL roof.

That makes sense thank u for the explaination.. so why not just re design the JL to fit the convertible definition. Lets get rid of the A and B pillar connecting structure instead of making it a hardtop with a giant sunroof. Guys who want a full steel roof can still order one. Win win.

 

[Otto]

Like I said in the other thread... the removal of the sport / roll bar and replaced with a roof structure really bothers me. I'm picturing a Wrangler roof with lots of removable sunroof panels and window panels but no longer a whole top removal.

 

[94grt]

Like I said in the other thread... the removal of the sport / roll bar and replaced with a roof structure really bothers me. I'm picturing a Wrangler roof with lots of removable sunroof panels and window panels but no longer a whole top removal.

It's a well known fact that altho most people say they bought a Wrangler for its complete open air feel very few who buy it actually remove the roof and use it for that purpose with any frequency if at all. Perception is reality so if Wrangler owners protest enough FCA will take notice but I also know that they know the fact that I just mentioned and must ask themselves at what cost to them will be another 10 years with a fully removable roof.

 

[JTman]

Is everyone just making the assumption that sport bar and fold down windshield will be gone because of the rumors or potential change in laws? Because it's still legal for the Wrangler to have it. If this speculation exists just because of NHTSA's *potential* change of rules, don't be surprised if the 2018 Wrangler retains either or both.

 

[SWinch]

Is everyone just making the assumption that sport bar and fold down windshield will be gone because of the rumors or potential change in laws? Because it's still legal for the Wrangler to have it. If this speculation exists just because of NHTSA's *potential* change of rules, don't be surprised if the 2018 Wrangler retains either or both.

They have been saying that for years. I remember back in 2013 reading an article about this and the law is still not changed. One way FCA can get around this is to decrease the refresh cycle of the Wrangler so they don't need to prepare for law changes 10 years down the line which no one can predict.

 

[Joe Camel]

Can they not design one with a fixed roof and another version where it is removable? Would that be too costly?

 

[JoKer]

Can they not design one with a fixed roof and another version where it is removable? Would that be too costly?

Even if they did so, if the law changes like the OP predicts both fixed and removable roof would have to meet the conventional roof crush requirements. So problem not solved. In fact it would make the fixed substructure for the roof pointless if they can make a removable version that meets those standards.

 

[RussJeep1]

I see a lot of banter about the JL moving away from a fully removable roof and very few discussing the REAL reason behind such a potential change.

It's not about costs, design challenges or any of that, at least not in any majorly impactful way to cause such a big shift in Wrangler design. This is about the NHTSA convertible exemption that the Wrangler has benefited from up until now, but which the NHTSA is potentially looking to overturn.

The FMVSS 216 exemption allows vehicles classified as open-top / convertibles to use an alternate crash test and less stringent requirements in which it has to resist less force than other vehicles. The fear is that the ever restrictive safety mandates will cause the NHTSA to get rid of the exemption and require extra strength in the A pillar of the JL Wrangler. FCA has no plans to shorten the life cycle of the next Wrangler so the threat of a law change out into the future must be assumed and seriously considered. I believe they have designed the JL with the worst case scenario in mind.

This doesn't have to mean the death of open air design altogether but major structural and design changes need to be made to the roof. An open fixed structure and a fixed non-folding A pillar with higher crush loads more in line with a conventional hardtop and "soften the blow" literally with retractable opening roof panels (cloth and glass) could be the ultimate solution.

Based on the educated speculation I believe we'll see exactly this change in the JL Wrangler.

94grt..maybe the roof is fixed but panels come out, manually and automatically like in some Renegade trims:

 

[digitalbliss]

I don't understand what the folding windshield has to do with anything now with the release of the JL. The A pillar stays intact when it's down (unlike the JK and previous Jeeps).

 

[BlackRook]

I don't understand what the folding windshield has to do with anything now with the release of the JL. The A pillar stays intact when it's down (unlike the JK and previous Jeeps).

Absolutely true. BUT two years ago we didn't know that (check the dates of the previous messages). This is the resurrection of a VERY old thread.

 

[digitalbliss]

Absolutely true. BUT two years ago we didn't know that (check the dates of the previous messages). This is the resurrection of a VERY old thread.

Haha, I saw may 26... just didn't see the 2016 part!

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