Do I need to spend the money on a chip? Will it help my situation?

Jockey 19

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2010 JK Unlimited 4x4 Sport . w/3.8 - 373 gears and Automatic Transmission. Finally got the tires and wheels installed as well as the 2 in puck lift and jeep looks GREAT !!! The Jeep came standard with the 225/75 R16 tires and I replaced then withe 285/70 R17 - Basically going from a 29in set up to a 32in set up. So went up 3 inches with the tires and 2 with the puck lift. I was worried I would experience a loss of power as I really do not want to re-gear. Only thing I have noticed is when I get the Jeep on the highway, it likes to hunt gears when in Overdrive. Basically, at 60-70 mph, it is trying to cruze at around 1700 RPM and with the slightest incline, it will downshift. I have heard of people buying a chip or having 4x4 shop re-program transmission shift positions to improve this condition. Just wanting to get some opinions on this. My speedo is a little off, but I am not as much worried about that as I am the transmission. It is not awful, but it seems to be difficult for it to stay in Overdrive. If this is something that is recommended, what are good brands, is this something I can do myself, does this fix this condition? What should I expect to spend. THX
 
2010 JK Unlimited 4x4 Sport . w/3.8 - 373 gears and Automatic Transmission. Finally got the tires and wheels installed as well as the 2 in puck lift and jeep looks GREAT !!! The Jeep came standard with the 225/75 R16 tires and I replaced then withe 285/70 R17 - Basically going from a 29in set up to a 32in set up. So went up 3 inches with the tires and 2 with the puck lift.
No, you didn't. Clearance is measure at the lowest point, which is your differential. Bigger tires lift the differential by half the tire size increase. A 3" bigger tire gives 1.5" more clearance. Because the only lift comes from the half of the tire below the hub.
Lifts (regardless of type) do not increase ground clearance, they only provide clearance for bigger tires. They do also raise your center of gravity (which is a Bad Thing) and a well designed suspension lift can provide additional flex, but that doesn't apply to a puck lift.
I was worried I would experience a loss of power as I really do not want to re-gear. Only thing I have noticed is when I get the Jeep on the highway, it likes to hunt gears when in Overdrive. Basically, at 60-70 mph, it is trying to cruze at around 1700 RPM and with the slightest incline, it will downshift. I have heard of people buying a chip or having 4x4 shop re-program transmission shift positions to improve this condition. Just wanting to get some opinions on this. My speedo is a little off, but I am not as much worried about that as I am the transmission. It is not awful, but it seems to be difficult for it to stay in Overdrive. If this is something that is recommended, what are good brands, is this something I can do myself, does this fix this condition? What should I expect to spend. THX
You've lost some torque because of the change to your final ratio. And now all the calibrations are off.

You can download JScan and get a single vehicle license for about $25. You can get one of their recommended OBDII dongles for about $25 as well. That will allow you to reset the speedometer and such, but will not regain the torque you've lost.

It's not a huge loss though, and how much it matters will depend on you. If you're driving on the street at low altitude in a relatively flat area, it won't matter as much as if you're driving up a 45 degree rock at 8000 feet.
 
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@Dirty Dog i understand what you are saying about ground clearance, lifts, flex etc. and agree the ground clearance at the differential is as you stated above, 1.5”. But suspensions lifts “increase the ground clearance in the middle”. It is usually the “belly of the jeep” that is an issue with clearance and hitting. Yes I know you know this that the axle goes up and down with the tires and based my experience “usually” when wheeling the tires end up on the large rocks to go over thus the axle goes up its after you cleared it and what happens when you come back down and the belly of the jeep hits getting high centered etc. Vast majority of the time a person gets high centered in the middle and thus with a suspension lift that gets reduced. I guess for me while there may not be an official / technical term for this I’ve always broken ground clearance into two categories, differential and center of the Jeep.
 
@Dirty Dog i understand what you are saying about ground clearance, lifts, flex etc. and agree the ground clearance at the differential is as you stated above, 1.5”. But suspensions lifts “increase the ground clearance in the middle”. It is usually the “belly of the jeep” that is an issue with clearance and hitting. Yes I know you know this that the axle goes up and down with the tires and based my experience “usually” when wheeling the tires end up on the large rocks to go over thus the axle goes up its after you cleared it and what happens when you come back down and the belly of the jeep hits getting high centered etc. Vast majority of the time a person gets high centered in the middle and thus with a suspension lift that gets reduced. I guess for me while there may not be an official / technical term for this I’ve always broken ground clearance into two categories, differential and center of the Jeep.
I believe it's referred to as "breakover angle", and lifts can help with that. Of course, you'll generally need some extra armor if breakover angle is a concern. Because a puncture in your oil or transmission pan will ruin your day.
 
No, you didn't. Clearance is measure at the lowest point, which is your differential. Bigger tires lift the differential by half the tire size increase. A 3" bigger tire gives 1.5" more clearance. Because the only lift comes from the half of the tire below the hub.
Lifts (regardless of type) do not increase ground clearance, they only provide clearance for bigger tires. They do also raise your center of gravity (which is a Bad Thing) and a well designed suspension lift can provide additional flex, but that doesn't apply to a puck lift.

You've lost some torque because of the change to your final ratio. And now all the calibrations are off.

You can download JScan and get a single vehicle license for about $25. You can get one of their recommended OBDII dongles for about $25 as well. That will allow you to reset the speedometer and such, but will not regain the torque you've lost.

It's not a huge loss though, and how much it matters will depend on you. If you're driving on the street at low altitude in a relatively flat area, it won't matter as much as if you're driving up a 45 degree rock at 8000 feet.
Thanks Dirty Dog, we will be using this Jeep for standard adventure to include gravel roads, fishing, camping, and sunday drives. If the OBDII dongles will reset my speedometer and adjust my shift pattern, I think that is all that I need. I am going to take the advise and buy the JScan and see how that goes. Thanks
 
I’m running the same size tires , motor , trans , gear combo as yourself . 2008 JKU Sahara .
As the guys pointed out JSCAN. It does help but your in a 4000lb Jeep , dry.
200 HP.
373 Gears
32” tires
You will find on inclines even at HWY speeds it will still pop out of OD with JSCAN setup . Depending on severity of hill drop into 3rd , sometimes 2nd. It will do it all day if driving threw the mountains at 80-90kph. .
I don’t find it to bothersome as the trans does shift pretty smoothly .
But it is a sign of an underpowered vehicle .
The only real & correct fix is to compensate with diff gears . I know you said not in the budget and I understand .
But if it’s ever a possibility 410 or 4.56 would def help keep it in OD except for the steep hills will probably jump into 3rd on occasion .
 
I’m running the same size tires , motor , trans , gear combo as yourself . 2008 JKU Sahara .
As the guys pointed out JSCAN. It does help but your in a 4000lb Jeep , dry.
200 HP.
373 Gears
32” tires
You will find on inclines even at HWY speeds it will still pop out of OD with JSCAN setup . Depending on severity of hill drop into 3rd , sometimes 2nd. It will do it all day if driving threw the mountains at 80-90kph. .
I don’t find it to bothersome as the trans does shift pretty smoothly .
But it is a sign of an underpowered vehicle .
The only real & correct fix is to compensate with diff gears . I know you said not in the budget and I understand .
But if it’s ever a possibility 410 or 4.56 would def help keep it in OD except for the steep hills will probably jump into 3rd on occasion .
That is what I am beginning to think. The resetting of the odometer w/the J-scan did seem to help a wee bit. However, it still having trouble staying in OD. I guess as long as I am not going to prematurely wear out the transmission, I could deal with it. For all around use, would you recommend the 410 or the 456 gears. One other question. I have a set of 1.5 in hub centric spacers that I have considered using. I am currently running 17x8 wheels that are aftermarket but they have the same offset as a factory wheel. Basically they are even w/the flares. Would it be unhealthy for me to run this small of a spacer and push the wheel out 1.5 on each side?
 
That is what I am beginning to think. The resetting of the odometer w/the J-scan did seem to help a wee bit. However, it still having trouble staying in OD. I guess as long as I am not going to prematurely wear out the transmission, I could deal with it.
Your transmission is spinning faster. Which means more friction. Which means more heat. Which means more wear. It's not a huge difference, but it IS wearing things faster.
For all around use, would you recommend the 410 or the 456 gears.
This should help.
38gears-1200x1709-png.png

One other question. I have a set of 1.5 in hub centric spacers that I have considered using. I am currently running 17x8 wheels that are aftermarket but they have the same offset as a factory wheel. Basically they are even w/the flares. Would it be unhealthy for me to run this small of a spacer and push the wheel out 1.5 on each side?
All wheel spacers are bad. The thicker the spacer, the worse the are. But they are always a suboptimal choice. The correct solution is wheels with the proper backspacing and offset.
 
Well, I may have went slightly big on the tires. Looks like I could have really used 410 gears in the 1st place. In this case, it looks like the 456 might be a better choice. Probably running about 2500 rpm at 75 mph. Might be a little on the high side, but I think that is better than all the pressure on the transmission
 
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Been running spidertrac 1.5 spacers on my 07 Rubi for over 50k. Still have original wheel bearings, ball joints, tie rod ends etc. 0 issues. Never had a single lug come out of torque. I think people get into trouble running them on oversized tires and wheels that are already back spaced. 🍺🍺
 
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Your transmission is spinning faster. Which means more friction. Which means more heat. Which means more wear. It's not a huge difference, but it IS wearing things faster.

This should help.
View attachment 124517

All wheel spacers are bad. The thicker the spacer, the worse the are. But they are always a suboptimal choice. The correct solution is wheels with the proper backspacing and offset.
I do not think I have taken my JK up to 70MPH once in the last 13yrs. Never on the highway prefer my back routes and the scenery, dodging large and small critters. All Good
 
Your transmission is spinning faster. Which means more friction. Which means more heat. Which means more wear. It's not a huge difference, but it IS wearing things faster.

This should help.
View attachment 124517

All wheel spacers are bad. The thicker the spacer, the worse the are. But they are always a suboptimal choice. The correct solution is wheels with the proper backspacing and offset.

What @Dirtydog said .
If you look at the chart there is only a diff of about 200-300 rpm between 410 vs 456 for any given tire size .
Depending on your driving habits , if you off road much and if larger tires are a possibility in your future will determine what you should go with .
Myself going up to a 35” K02 , measures 34” . When my current K02’s wear down .
So I’ll provably go with a 4.56.
If I was staying with a 33” would probably settle on a 4.10.
I also do quite a bit Hwy driving to get to the trails so don’t want to wind it out to much .
Def agree with Dog regarding spacers . Just get wheels with 4.5” backspacing . It sticks about about 11/2” beyond the flare .
If your on 32” I don’t think you need spacers with 6” backspaced wheels .
Just pop off spacer from front, put wheel & tire back on and see if clearance issues while turning .
And yes some guys like @ Bigal07 run spacers without issues . Personally never would . Premature wear can
be an issue.