Cruise control disengages after 6in lift and 35in tires

[17 High Country]

Hey guys,

 

I have a 2017 Silverado High Country and I installed a 6in Fabtech lift with 35in nitto tires back in September 2017 and since then I've been having issues with my cruise control disengaging/turning off at anything above 69mph. When I'm traveling above 69mph, cruise control will turn on and illuminate on the dash, but it wont engage or lock on. Even when I have the cruise set at 65mph and I try to increase the speed to 70mph, it'll immediately cut off/disengage.

 

I took it to the dealership around January 2018 and they told me since the truck has bigger/heavier tires, the computer is reading the wheels going slower than what it reads on the speedometer. They basically said I need to recalibrate the computer to read the new tire size. BUT, a friend of mine also said I could possibly need to re-gear to 4.56 since I'm running heavier tires, which could fix the cruise control cutting off.

 

If anyone has experienced this issue, you help will be greatly appreciated. Thanks guys.

[BO TIE 1]

I would try getting a handheld tuner and changing the tire size. I have a diablo sport intune that allows you to change the tire size and many other parameters.

[Sierra706]

The computer is reading exactly what’s on the speedo. The wheel speed sensor is housed in the rear differential. So while your speed is different your truck has no idea.

So at 70 mph indicated your actually doing about 78 due to your tire increase. Maybe your truck is thinking that there’s too much load on the engine for the given speed it assumes due to wind resistance? Although that wouldn’t t make much sense because then cruise control wouldn’t work while towing a trailer.

[Scribe325]

I am running the same setup on my 2017 Silverado LT 4x4. I have a Fabtech 6 inch lift with 35s. I have been on that setup for almost two years and have not had a single issue with cruise control. I do intend to re-gear/tune soon (I am going to 4.10 gears) primarily to restore the feel of the stock setup, towing capacity and relieve some stress on the transmission.

 

All that is to say I doubt your lift/wheel/tire setup is causing cruise control problems. I think the issue likely lies elsewhere. As was mentioned earlier, the cruise control and wheel speed sensor have no way of knowing how big your tires are. Perhaps you have a bad wheel speed sensor?

 

Not that it helps to hear “I don’t have a problem even though you do” but I have had my share of answers from dealer technicians that I knew immediately to be incorrect. I am always frustrated when the supposed experts on a vehicle were either too lazy or too uninformed to do some research to get you a correct answer. I’m not sure which is worse.

 

[17 High Country]

1 hour ago, BO TIE 1 said:

I would try getting a handheld tuner and changing the tire size. I have a diablo sport intune that allows you to change the tire size and many other parameters.

I borrowed my friend’s Edge CS2 Tuner and I adjusted the tire size to 35in but still didn’t do the issue, unfortunately 

[17 High Country]

41 minutes ago, Scribe325 said:

I am running the same setup on my 2017 Silverado LT 4x4. I have a Fabtech 6 inch lift with 35s. I have been on that setup for almost two years and have not had a single issue with cruise control. I do intend to re-gear/tune soon (I am going to 4.10 gears) primarily to restore the feel of the stock setup, towing capacity and relieve some stress on the transmission.

 

All that is to say I doubt your lift/wheel/tire setup is causing cruise control problems. I think the issue likely lies elsewhere. As was mentioned earlier, the cruise control and wheel speed sensor have no way of knowing how big your tires are. Perhaps you have a bad wheel speed sensor?

 

Not that it helps to hear “I don’t have a problem even though you do” but I have had my share of answers from dealer technicians that I knew immediately to be incorrect. I am always frustrated when the supposed experts on a vehicle were either too lazy or too uniformed to do some research to get you a correct answer. I’m not sure which is worse.

Thanks for the input, but I’ll definitely try changing out the wheel speed sensors. I’ve been wanting to re-gear anyways so hopefully that will fix it if the speed sensors don’t.

 

Do you think if I tell the dealership that the wheel speed sensors are malfunctioning they’ll replace them?

[geswek]

You need to check all wires from when the lift was put on.

I drove my truck for 3 months in stock gears before I put new ones in. Changing tire size with tuner only affects what you see on dash and transmission shifting pattern. It doesn’t tell cruise when to shut off.

Your cruise control not working is either bad wire that was moved after lift or you got a real cruise control failure. Unfortunately the dealer is already giving you crap because you lifted it.


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[Scribe325]

Thanks for the input, but I’ll definitely try changing out the wheel speed sensors. I’ve been wanting to re-gear anyways so hopefully that will fix it if the speed sensors don’t.
 
Do you think if I tell the dealership that the wheel speed sensors are malfunctioning they’ll replace them?

I’m not a dealer expert (a few folks around here are pretty knowledgeable on the inner workings of dealerships) but I would expect that a wheel speed sensor is covered under your powertrain warranty.

I also expect the dealer will try to weasel out of that coverage by telling you your wheel/tire setup voids that portion of the warranty even though I have a hard time believing big tired would cause that failure. I’m not sure how you’d fight that one. I would definitely ask the dealer to do a warranty swap of the wheel speed sensor and go from there.

[Armo325]

 

I’m not a dealer expert (a few folks around here are pretty knowledgeable on the inner workings of dealerships) but I would expect that a wheel speed sensor is covered under your powertrain warranty.

 

I also expect the dealer will try to weasel out of that coverage by telling you your wheel/tire setup voids that portion of the warranty even though I have a hard time believing big tires would cause that failure. I’m not sure how you’d fight that one. I would definitely ask the dealer to do a warranty swap of the wheel speed sensor and go from there.

 

To add to this (I accidentally used an old account here - sorry, mods), this all assumes the wheel speed sensor is, in fact, the problem. geswek makes a great point that the problem could be caused by the lift install and an issue with wiring. I agree that you should take a good look at everything before going to ask for parts from the dealer.

 

One of the things I noticed on my lift is the guys that installed it did NOT replace some of the plastic wire restraints on the rear axle after the lift. At first I thought it was an oversight but I realized later it was probably intentional to leave more slack in the wiring to account for the lift. You may want to verify none of your wires have pulled loose from the additional distance between your frame and the wiring going to the rear diff.

[Sierra706]

I’m not a dealer expert (a few folks around here are pretty knowledgeable on the inner workings of dealerships) but I would expect that a wheel speed sensor is covered under your powertrain warranty.

I also expect the dealer will try to weasel out of that coverage by telling you your wheel/tire setup voids that portion of the warranty even though I have a hard time believing big tired would cause that failure. I’m not sure how you’d fight that one. I would definitely ask the dealer to do a warranty swap of the wheel speed sensor and go from there.

They can’t blame a bad sensor on the lift and would have to replace it if found faulty. But they can refuse to diagnose the problem under warranty and just claim that the lift is causing the issue without even looking at it. Worst case scenario you agree to pay for the diagnostics in the event the issue is not the sensor.


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[argonzal]

Did you ever resolve this? I'm having similar issue with 2018 Silverado.  6in lift and 35s and cruise was working fine.  Regeared to 4.56 and cruise stopped working.  Installed hypertech b inline module to correct speedometer but still not working.  

[tlaw91]

Wheel speed sensor isn’t a problem, neither is your psycho industrial lift.

Sounds like you need a brake switch to me, but you haven’t given me much to go on.

You prob need brake switch and the brake pedal learn procedure done. They go bad all the time on beginning-of-time-2013 trucks lol

-Friendly neighborhood GM tech guessing lol



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[tlaw91]

Did you ever resolve this? I'm having similar issue with 2018 Silverado.  6in lift and 35s and cruise was working fine.  Regeared to 4.56 and cruise stopped working.  Installed hypertech b inline module to correct speedometer but still not working.  

Well that’s interesting [emoji848] that’s a new one for me


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[AzCoronaDog]

Not the same issue exactly, but kind of related, so I will share my cruise control story here too.

I put a 7" lift and 35" tires on my '17 Yukon XL, and my adaptive cruise control would only report that is was temporarily not available.

I thought it was a sensor alignment issue, but I tried adjusting it and still could not get it to work. 

Another person had the same issue, and when they took out the custom wheel size programming, it started working again.

I undid the custom programming, and mine is working again too, but of course my speedometer is not as accurate as it was.

I need to use my GPS again to see how far off it is and decide if can live with it until I can see if there is another solution, perhaps an external speedometer correction that does not require reprogramming the BCM.