Issues moving up to 35's

[jorgelrod]

My understanding is that the ONLY use for a procal/flashcal on a manual was to adjust TPMS and speedo. That's it.... the jeep will work just fine without it, however your speedo will be off whatever the difference is, and the tpms system light will be on. That's my understanding. Can someone verify?

Nope, on an Auto, it can cause your tranny to go into Limp Mode to protect itself because, the shift points and the ESC will be off

 

[JakeJK]

My understanding is that the ONLY use for a procal/flashcal on a manual was to adjust TPMS and speedo. That's it.... the jeep will work just fine without it, however your speedo will be off whatever the difference is, and the tpms system light will be on. That's my understanding. Can someone verify?

You're mileage and MPG I don't know how much it would affect the mileage but I'd be a little upset down the road if I knew my jeep had 70k miles instead of 50 like the ODO said, (I doubt it would be that drastic) just saying

 

[JakeJK]

Nope, on an Auto, it can cause your tranny to go into Limp Mode to protect itself because, the shift points and the ESC will be off

He said on a manual

 

[toxicwaste29]

I have 35s on my jk and haven't reprogrammed the speedo or tpms. It's is a manual. Going about 60 it is reading 65 in the speedo. Not really an issue if your going the speed limit your going five over. I only want a procal to reset the tpms currently. When I get gears and 37s than I will definitely redo the speedo

 

[DWiggles]

You're mileage and MPG I don't know how much it would affect the mileage but I'd be a little upset down the road if I knew my jeep had 70k miles instead of 50 like the ODO said, (I doubt it would be that drastic) just saying

Mileage is something I hadn't though of... I don't really care what the computer THINKS about mpg, gas in = money spent lol. I'm just not sure $150 is worth an accurate speedometer and a tpms light... that's pretty much where I'm at right now.

 

[albertmald9]

Mileage is something I hadn't though of... I don't really care what the computer THINKS about mpg, gas in = money spent lol. I'm just not sure $150 is worth an accurate speedometer and a tpms light... that's pretty much where I'm at right now.

Yea if you can deal with the speedo being off, it doesn't really matter. My TJ is a manual and I never changed the speedo gear on the t-case. I'm pretty sure it has closer to 88k miles even though the odometer reads 80k. That doesn't bother me. However, my JK is an automatic and if I can correct the shift points I will gladly spend the money. Calibrating the gear ratio, tire size, speedo, and shift points with this device makes it well worth $150 to me.

 

[hawklee]

I just put on 35's this weekend and the speedo is off 5 mph, says I'm going slower than i really am. Also noticed today while commuting that it does shift slightly different.

I have the super chips flash cal and will try to use in the next few day, probably on the weekend and will repost. I personally don't care about the speedo or the tpms light on, but if it helps performance and/or prevents future issues, its worth a try.

 

[lulu2533]

Yea if you can deal with the speedo being off, it doesn't really matter. My TJ is a manual and I never changed the speedo gear on the t-case. I'm pretty sure it has closer to 88k miles even though the odometer reads 80k. That doesn't bother me. However, my JK is an automatic and if I can correct the shift points I will gladly spend the money. Calibrating the gear ratio, tire size, speedo, and shift points with this device makes it well worth $150 to me.

Can't you get into alot of trouble if your odometer is knowingly inaccurate? Not sure.

 

[hawklee]

The c-gussets just help to keep them from bending.

it looks like the C gussets are fairly inexpensive, but they have to be welded into place? How much would that run and how long does it take to get complete or back on the road?
also, why just the front and not the rear?

 

[Suprchrgd_rubi]

I use the pro cal but mines is an auto, I am running 35 with just installed yesterday 4:88. Wow big difference from 3:73. Anyway at 70mph looks like it's about 2800rpm maybe should go 4:56 or get 37. Just FYI on info

 

[WJCO]

it looks like the C gussets are fairly inexpensive, but they have to be welded into place? How much would that run and how long does it take to get complete or back on the road?
also, why just the front and not the rear?

Rear is a stronger/bigger axle, doesn't have a knuckle like the front, doesn't take the steering loads, and doesn't have the weight of the engine etc. Rear axle shafts typically break/bend more than something on the housing.

I don't know what's really involved in welding them on, but looks like half hour per side I'm guessing. Someone here will know.

 

[albertmald9]

Can't you get into alot of trouble if your odometer is knowingly inaccurate? Not sure.

I'm sure you can. In California, reporting odometer readings isn't mandatory for vehicles greater than 10 years old. However, when I sell the TJ i'll definitely tell the buyer that the odometer is off by 5k-8k.

 

[cozdude]

Rear is a stronger/bigger axle, doesn't have a knuckle like the front, doesn't take the steering loads, and doesn't have the weight of the engine etc. Rear axle shafts typically break/bend more than something on the housing.

I don't know what's really involved in welding them on, but looks like half hour per side I'm guessing. Someone here will know.

It's about a 4 hour job if you leave the ball joints in. You want to take your time as you don't want to hear them up. If you take them out then you can get it done in about an hour per side but you still want to go slow so you don't warp anything.

 

[WJCO]

It's about a 4 hour job if you leave the ball joints in. You want to take your time as you don't want to heat them up. If you take them out then you can get it done in about an hour per side but you still want to go slow so you don't warp anything.

Thanks for that advice. Good words. I will probably do them to be safe when I make my switch.

 

[Shantz]

You don't need the procal just cause you have a Manual. An auto NEEDS a procal to insure that the shift points are correct for the larger tires. A procal is NEEDED for both auto and manual when you do a gear swap.

Did not know that... I'm a little ignorant in this subject... what are shift points and how do they change in a manual? If I continue without a procal will I do damage to the vehicle?

 

[Flynlo]

In layman's terms, shift points are the points in which the transmission decides it's necessary to change a gear. In a manual, the driver is the one who determines the shift points.

The pro cal or something similar, I believe, is necessary when changing gears or tire sizes. If your speedo thinks it's going 5 mph faster or slower than it actually is then over time your odometer will be way off, especially if you leave it that way for a long time. It may not be a big deal if you plan on keeping your Jeep forever but if I were to consider buying a Jeep, but the odometer was inaccurate, I'd walk away. It's around $140 and it keeps the Jeep's computer accurate, worth while if you ask me.

 

[Shantz]

In layman's terms, shift points are the points in which the transmission decides it's necessary to change a gear. In a manual, the driver is the one who determines the shift points.

The pro cal or something similar, I believe, is necessary when changing gears or tire sizes. If your speedo thinks it's going 5 mph faster or slower than it actually is then over time your odometer will be way off, especially if you leave it that way for a long time. It may not be a big deal if you plan on keeping your Jeep forever but if I were to consider buying a Jeep, but the odometer was inaccurate, I'd walk away. It's around $140 and it keeps the Jeep's computer accurate, worth while if you ask me.

That's what I thought... cozdude made me nervous when he said auto and manual need a procal... I plan on running my Jeep till I'm dead... so for now I'm not worried about the 5 up on the speedo.

 

[hawklee]

I just put on 35's this weekend and the speedo is off 5 mph, says I'm going slower than i really am. Also noticed today while commuting that it does shift slightly different.

I have the super chips flash cal and will try to use in the next few day, probably on the weekend and will repost. I personally don't care about the speedo or the tpms light on, but if it helps performance and/or prevents future issues, its worth a try.

Ok so I'm getting 35's for the first time and I'm under the impression I'm gonna need to do a couple things... Not exactly sure what they are. (Tried searching but I'm probably doing it wrong)

My question is, is spedo adjustment required? and by required I mean is anything other than the display affected by not doing it?

I saw a few mentions of these procal modules. Are there any alternatives to these kind of things? (I saw something about them screwing something up with the sway bar or lockers on a JK rubicon. Ring any bells??

and Is there anything else I need to worry about with upsizing? not so much with clearances but more so with electronics and gears and what not

and to note (one day I might eat these words) but I'm not going bigger than 35"

UPDATE: Went to use Superchips Flashcal today and can't download the software as it only runs microsoft and I use Mac. So will find a friend with Windows and try tomorrow.

 

[JAGS]

UPDATE: Went to use Superchips Flashcal today and can't download the software as it only runs microsoft and I use Mac. So will find a friend with Windows and try tomorrow.

The main downside of the flash cal in my opinion. Even with two PCs I still had software issues with the updates. The reasons why I ended up selling mine and going procal.

 

[Skid_Kid]

The main downside of the flash cal in my opinion. Even with two PCs I still had software issues with the updates. The reasons why I ended up selling mine and going procal.

I have a little netbook that I bought and I have not had any issues.