Installed 37's on Gen3 35 Raptor - no issues.

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crv

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Thought I'd give a quick update on my thoughts having around 4k miles bone stock (35 Package) to now switching to a 37 setup pictured above last week. I recently did a 600 mile road trip and spent some time off-road in dried lake beds and FS Roads with around 12-16" of snow in places. I'll preface this by saying my experiences of this probably won't mirror the mass sentiment here. I spend a copious amount of time off-road and have raced anything with 2 or 4 wheels in that environment for many many years, needless to say I'm a picky SOB when it comes to change and vehicle dynamics.

First off, the general sentiment of adding 37's is no noticeable change I don't agree with. Is it a drastic change, not by any means. Is there definite drawbacks that can be noticed, absolutely 100% so don't trust the placebo effects from many of oh "it looks badass can't even tell". First off, the most apparent the MPG decrease is there for those that care. My anecdotal observation is I lost a solid 1.5mpg on average with a trip I frequently take which is inline with how Ford rates EPA of a 35 vs 37, so no surprise. The reason why though I feel is important. Adding 37's has a very noticeable impact on the final drive ratio and therefore really takes away the down low snappiness of the 10AT combined with 35's. It's now 200-300rpm lower in any given gear and almost always needs to be a gear lower than previous to have that same "take-off" and go. You start noticing things like turbo lag and torque converter slippage when it isn't locked in lower gears more than before. Once going at HWY speeds this is less noticeable however instead of 2,000k RPM at 70mph I'm now right at 1,700 RPM. So it will downshift to 8/9th more often all things being equal to stay in the correct TQ band. For reference, I also reset the PCM/TCU adaptations and reset my tire size per the Forscan instruction included on this forum. Oddly, I've also noticed much more clunking on downshifts from the 10AT after doing so but I don't believe this to be attributed to anything tire related...yet.

Although, my 37 wheel/tire combo is basically as light as you can buy currently I wouldn't say it rides better. OEM FP 37's although C rated have thicker sidewalls than the metric 315/70 (35") counterparts when I looked at both dismounted. I find under certain conditions 37's ride better but on broken or uneven pavement my 35's actually rode better and were less nervous traveling at FWY speeds of 70-80mph. The 37's I suppose from being skinnier actually tramline worse which is ironic given I thought they would less. Note: I run the same pressures for each at 38psi Cold. The biggest item to consider is off-road the 37's are less composed on moderately fast terrain. Think dry lake beds doing 40-60mph and hitting large dips at those speeds. The rebound dampening isn't quite there to support the larger tires overall. I would image this is where the 37pp is retuned to account for that. Changing to Sport or Baja mode helps this but doesn't fully mask it. Ultimately, any of the faster paced stuff 37's are a clear downgrade which again is to be realistically expected but was more than anticipated.

With that said, would I go back? I'm not 100% sure overall. Personally, I've never let looks generally dictate a modification given I "use" my vehicles for their intended purpose. However, I was woefully unimpressed with how pedestrian a stock 35 Raptor looks. To the point even with smaller tires my previous GMC AT4 almost had more presence. With the 37's the truck just looks right, fender proportions, how it sits, stance, etc. just fit the body lines of the truck perfectly. It has completely altered how I feel about the looks of the vehicle and I'm 100% pleased. From, I performance perspective I'd being lying if it's not in the back of my head to go back to 35's though...
Now you have me second guessing going to 37's....lol
 

hyrepower

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Thought I'd give a quick update on my thoughts having around 4k miles bone stock (35 Package) to now switching to a 37 setup pictured above last week. I recently did a 600 mile road trip and spent some time off-road in dried lake beds and FS Roads with around 12-16" of snow in places. I'll preface this by saying my experiences of this probably won't mirror the mass sentiment here. I spend a copious amount of time off-road and have raced anything with 2 or 4 wheels in that environment for many many years, needless to say I'm a picky SOB when it comes to change and vehicle dynamics.

First off, the general sentiment of adding 37's is no noticeable change I don't agree with. Is it a drastic change, not by any means. Is there definite drawbacks that can be noticed, absolutely 100% so don't trust the placebo effects from many of oh "it looks badass can't even tell". First off, the most apparent the MPG decrease is there for those that care. My anecdotal observation is I lost a solid 1.5mpg on average with a trip I frequently take which is inline with how Ford rates EPA of a 35 vs 37, so no surprise. The reason why though I feel is important. Adding 37's has a very noticeable impact on the final drive ratio and therefore really takes away the down low snappiness of the 10AT combined with 35's. It's now 200-300rpm lower in any given gear and almost always needs to be a gear lower than previous to have that same "take-off" and go. You start noticing things like turbo lag and torque converter slippage when it isn't locked in lower gears more than before. Once going at HWY speeds this is less noticeable however instead of 2,000k RPM at 70mph I'm now right at 1,700 RPM. So it will downshift to 8/9th more often all things being equal to stay in the correct TQ band. For reference, I also reset the PCM/TCU adaptations and reset my tire size per the Forscan instruction included on this forum. Oddly, I've also noticed much more clunking on downshifts from the 10AT after doing so but I don't believe this to be attributed to anything tire related...yet.

Although, my 37 wheel/tire combo is basically as light as you can buy currently I wouldn't say it rides better. OEM FP 37's although C rated have thicker sidewalls than the metric 315/70 (35") counterparts when I looked at both dismounted. I find under certain conditions 37's ride better but on broken or uneven pavement my 35's actually rode better and were less nervous traveling at FWY speeds of 70-80mph. The 37's I suppose from being skinnier actually tramline worse which is ironic given I thought they would less. Note: I run the same pressures for each at 38psi Cold. The biggest item to consider is off-road the 37's are less composed on moderately fast terrain. Think dry lake beds doing 40-60mph and hitting large dips at those speeds. The rebound dampening isn't quite there to support the larger tires overall. I would image this is where the 37pp is retuned to account for that. Changing to Sport or Baja mode helps this but doesn't fully mask it. Ultimately, any of the faster paced stuff 37's are a clear downgrade which again is to be realistically expected but was more than anticipated.

With that said, would I go back? I'm not 100% sure overall. Personally, I've never let looks generally dictate a modification given I "use" my vehicles for their intended purpose. However, I was woefully unimpressed with how pedestrian a stock 35 Raptor looks. To the point even with smaller tires my previous GMC AT4 almost had more presence. With the 37's the truck just looks right, fender proportions, how it sits, stance, etc. just fit the body lines of the truck perfectly. It has completely altered how I feel about the looks of the vehicle and I'm 100% pleased. From a performance perspective I'd being lying if it's not in the back of my head to go back to 35's though...
VERY well put. I agree 100%, which is why I am installing a set of Fox Race Series Coilovers, to hopefully get back some rebound damping that the stock dampers are lacking.
 

ToadSmasher2K1

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So much for 'Live Valve", truth be told, I think Live Valve sucks. It doest work any better than a traditional shock and just makes for something expensive that can go wrong.
I don’t disagree. If I’m being honest my Gen2 without live valve had a nicer ride.
 

pnwobrigade

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So much for 'Live Valve", truth be told, I think Live Valve sucks. It doest work any better than a traditional shock and just makes for something expensive that can go wrong.
I'm 50/50 on this, I think in some circumstances it's handy to have especially for the masses. The implementation of it's pretty clever and seems to be where lots of Motorsports oriented Fox stuff is going. I have Fox 3.0 RC2's (triple adjustable) on my Can Am X3 and I still prefer those as I can easily dial it in for just about any terrain. It can be a pain though to fine tune. The ability to not get out of the cab and push a button to significantly alter the dampening is pretty trick I won't lie. I seen SDI recently released the ability to "tune" this so I might keep an eye on that although the price point is a bit off in my opinion...
 

Chazzersgarage

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Thought I'd give a quick update on my thoughts having around 4k miles bone stock (35 Package) to now switching to a 37 setup pictured above last week. I recently did a 600 mile road trip and spent some time off-road in dried lake beds and FS Roads with around 12-16" of snow in places. I'll preface this by saying my experiences of this probably won't mirror the mass sentiment here. I spend a copious amount of time off-road and have raced anything with 2 or 4 wheels in that environment for many many years, needless to say I'm a picky SOB when it comes to change and vehicle dynamics.

First off, the general sentiment of adding 37's is no noticeable change I don't agree with. Is it a drastic change, not by any means. Is there definite drawbacks that can be noticed, absolutely 100% so don't trust the placebo effects from many of oh "it looks badass can't even tell". First off, the most apparent the MPG decrease is there for those that care. My anecdotal observation is I lost a solid 1.5mpg on average with a trip I frequently take which is inline with how Ford rates EPA of a 35 vs 37, so no surprise. The reason why though I feel is important. Adding 37's has a very noticeable impact on the final drive ratio and therefore really takes away the down low snappiness of the 10AT combined with 35's. It's now 200-300rpm lower in any given gear and almost always needs to be a gear lower than previous to have that same "take-off" and go. You start noticing things like turbo lag and torque converter slippage when it isn't locked in lower gears more than before. Once going at HWY speeds this is less noticeable however instead of 2,000k RPM at 70mph I'm now right at 1,700 RPM. So it will downshift to 8/9th more often all things being equal to stay in the correct TQ band. For reference, I also reset the PCM/TCU adaptations and reset my tire size per the Forscan instruction included on this forum. Oddly, I've also noticed much more clunking on downshifts from the 10AT after doing so but I don't believe this to be attributed to anything tire related...yet.

Although, my 37 wheel/tire combo is basically as light as you can buy currently I wouldn't say it rides better. OEM FP 37's although C rated have thicker sidewalls than the metric 315/70 (35") counterparts when I looked at both dismounted. I find under certain conditions 37's ride better but on broken or uneven pavement my 35's actually rode better and were less nervous traveling at FWY speeds of 70-80mph. The 37's I suppose from being skinnier actually tramline worse which is ironic given I thought they would less. Note: I run the same pressures for each at 38psi Cold. The biggest item to consider is off-road the 37's are less composed on moderately fast terrain. Think dry lake beds doing 40-60mph and hitting large dips at those speeds. The rebound dampening isn't quite there to support the larger tires overall. I would imagine this is where the 37pp is retuned to account for that. Changing to Sport or Baja mode helps this but doesn't fully mask it. Ultimately, any of the faster paced stuff 37's are a clear downgrade which again is to be realistically expected but was more than anticipated.

With that said, would I go back? I'm not 100% sure overall. Personally, I've never let looks generally dictate a modification given I "use" my vehicles for their intended purpose. However, I was woefully unimpressed with how pedestrian a stock 35 Raptor looks. To the point even with smaller tires my previous GMC AT4 almost had more presence. With the 37's the truck just looks right, fender proportions, how it sits, stance, etc. just fit the body lines of the truck perfectly. It has completely altered how I feel about the looks of the vehicle and I'm 100% pleased. From a performance perspective I'd being lying if it's not in the back of my head to go back to 35's though...

A couple of my own observations on this. I have a 23 37PP and I'm coming from a 18 Gen 2. For gas mileage I seem to be losing about .5 to .8 MPG. I got between 16.8 to 17 in my gen 2. I get 16.2 to 16.5 in my gen 3. The difference between my truck and yours could be anything from driving style to tire pressure. At 70 mph I do get more downshifting however, at 80 I get less.

I feel like the 37PP rides as well and has no more wandering than my gen 2 did at highway speeds. It's very stable at speed. On fast fire roads (60 to 80 mph) it actually seems a little better than my gen 2 was. My guess is the upgraded shocks have a lot to do with that. The 37's seem smoother and more planted. Both trucks are effectively the same except for the front suspension. I believe the front suspension contributes more with the 37 tire package than most people realize.

Another thing I have noticed is the transmission performance. My gen 3 transmission seems to shift smoother and a little more positively than my gen 2 transmission did. Once again this could simply be my perception. I have read some things that lead me to believe the 37PP transmissions have the same upgraded clutches and shift controls as the raptor r.

There seems to be an ongoing "love/hate" kind of thing with Raptor Owners and 37's. Most seem to think the factory did alright with the 37PP raptors. I think the suspension upgrades help with the issues but it's not the only or ideal solution. I'm interest in what the long term results of running 37's are with the 35 trucks.
 
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RGVRaptor

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Thought I'd give a quick update on my thoughts having around 4k miles bone stock (35 Package) to now switching to a 37 setup pictured above last week. I recently did a 600 mile road trip and spent some time off-road in dried lake beds and FS Roads with around 12-16" of snow in places. I'll preface this by saying my experiences of this probably won't mirror the mass sentiment here. I spend a copious amount of time off-road and have raced anything with 2 or 4 wheels in that environment for many many years, needless to say I'm a picky SOB when it comes to change and vehicle dynamics.

First off, the general sentiment of adding 37's is no noticeable change I don't agree with. Is it a drastic change, not by any means. Is there definite drawbacks that can be noticed, absolutely 100% so don't trust the placebo effects from many of oh "it looks badass can't even tell". First off, the most apparent the MPG decrease is there for those that care. My anecdotal observation is I lost a solid 1.5mpg on average with a trip I frequently take which is inline with how Ford rates EPA of a 35 vs 37, so no surprise. The reason why though I feel is important. Adding 37's has a very noticeable impact on the final drive ratio and therefore really takes away the down low snappiness of the 10AT combined with 35's. It's now 200-300rpm lower in any given gear and almost always needs to be a gear lower than previous to have that same "take-off" and go. You start noticing things like turbo lag and torque converter slippage when it isn't locked in lower gears more than before. Once going at HWY speeds this is less noticeable however instead of 2,000k RPM at 70mph I'm now right at 1,700 RPM. So it will downshift to 8/9th more often all things being equal to stay in the correct TQ band. For reference, I also reset the PCM/TCU adaptations and reset my tire size per the Forscan instruction included on this forum. Oddly, I've also noticed much more clunking on downshifts from the 10AT after doing so but I don't believe this to be attributed to anything tire related...yet.

Although, my 37 wheel/tire combo is basically as light as you can buy currently I wouldn't say it rides better. OEM FP 37's although C rated have thicker sidewalls than the metric 315/70 (35") counterparts when I looked at both dismounted. I find under certain conditions 37's ride better but on broken or uneven pavement my 35's actually rode better and were less nervous traveling at FWY speeds of 70-80mph. The 37's I suppose from being skinnier actually tramline worse which is ironic given I thought they would less. Note: I run the same pressures for each at 38psi Cold. The biggest item to consider is off-road the 37's are less composed on moderately fast terrain. Think dry lake beds doing 40-60mph and hitting large dips at those speeds. The rebound dampening isn't quite there to support the larger tires overall. I would imagine this is where the 37pp is retuned to account for that. Changing to Sport or Baja mode helps this but doesn't fully mask it. Ultimately, any of the faster paced stuff 37's are a clear downgrade which again is to be realistically expected but was more than anticipated.

With that said, would I go back? I'm not 100% sure overall. Personally, I've never let looks generally dictate a modification given I "use" my vehicles for their intended purpose. However, I was woefully unimpressed with how pedestrian a stock 35 Raptor looks. To the point even with smaller tires my previous GMC AT4 almost had more presence. With the 37's the truck just looks right, fender proportions, how it sits, stance, etc. just fit the body lines of the truck perfectly. It has completely altered how I feel about the looks of the vehicle and I'm 100% pleased. From a performance perspective I'd being lying if it's not in the back of my head to go back to 35's though...
Do you believe the 37PP trucks have different shift points to accommodate the larger tires? I’m wondering if those trucks would also drive like you’re describing.

I have a brand new set of 37s waiting to be put on and now you got me second guessing. I also drive my truck 20k miles a year. So drivability is extremely important to me.

And to finish off…. I wonder if Cobb could have a 37s specific TCM tune in the future…
 

franky16

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Thought I'd give a quick update on my thoughts having around 4k miles bone stock (35 Package) to now switching to a 37 setup pictured above last week. I recently did a 600 mile road trip and spent some time off-road in dried lake beds and FS Roads with around 12-16" of snow in places. I'll preface this by saying my experiences of this probably won't mirror the mass sentiment here. I spend a copious amount of time off-road and have raced anything with 2 or 4 wheels in that environment for many many years, needless to say I'm a picky SOB when it comes to change and vehicle dynamics.

First off, the general sentiment of adding 37's is no noticeable change I don't agree with. Is it a drastic change, not by any means. Is there definite drawbacks that can be noticed, absolutely 100% so don't trust the placebo effects from many of oh "it looks badass can't even tell". First off, the most apparent the MPG decrease is there for those that care. My anecdotal observation is I lost a solid 1.5mpg on average with a trip I frequently take which is inline with how Ford rates EPA of a 35 vs 37, so no surprise. The reason why though I feel is important. Adding 37's has a very noticeable impact on the final drive ratio and therefore really takes away the down low snappiness of the 10AT combined with 35's. It's now 200-300rpm lower in any given gear and almost always needs to be a gear lower than previous to have that same "take-off" and go. You start noticing things like turbo lag and torque converter slippage when it isn't locked in lower gears more than before. Once going at HWY speeds this is less noticeable however instead of 2,000k RPM at 70mph I'm now right at 1,700 RPM. So it will downshift to 8/9th more often all things being equal to stay in the correct TQ band. For reference, I also reset the PCM/TCU adaptations and reset my tire size per the Forscan instruction included on this forum. Oddly, I've also noticed much more clunking on downshifts from the 10AT after doing so but I don't believe this to be attributed to anything tire related...yet.

Although, my 37 wheel/tire combo is basically as light as you can buy currently I wouldn't say it rides better. OEM FP 37's although C rated have thicker sidewalls than the metric 315/70 (35") counterparts when I looked at both dismounted. I find under certain conditions 37's ride better but on broken or uneven pavement my 35's actually rode better and were less nervous traveling at FWY speeds of 70-80mph. The 37's I suppose from being skinnier actually tramline worse which is ironic given I thought they would less. Note: I run the same pressures for each at 38psi Cold. The biggest item to consider is off-road the 37's are less composed on moderately fast terrain. Think dry lake beds doing 40-60mph and hitting large dips at those speeds. The rebound dampening isn't quite there to support the larger tires overall. I would imagine this is where the 37pp is retuned to account for that. Changing to Sport or Baja mode helps this but doesn't fully mask it. Ultimately, any of the faster paced stuff 37's are a clear downgrade which again is to be realistically expected but was more than anticipated.

With that said, would I go back? I'm not 100% sure overall. Personally, I've never let looks generally dictate a modification given I "use" my vehicles for their intended purpose. However, I was woefully unimpressed with how pedestrian a stock 35 Raptor looks. To the point even with smaller tires my previous GMC AT4 almost had more presence. With the 37's the truck just looks right, fender proportions, how it sits, stance, etc. just fit the body lines of the truck perfectly. It has completely altered how I feel about the looks of the vehicle and I'm 100% pleased. From a performance perspective I'd being lying if it's not in the back of my head to go back to 35's though...
Spot on
 

raptor730

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Im surprised more people dont move to 325/60/20 which gives a 35.4 or 1 inch taller than stock. Stock 35 is actually 34.4

Yeah I know you have to swap wheels but thats a bonus
 
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