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2018 Chevy 1500 4x4 Speed Control not working at higher speeds


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Posted

Need Help;

My New 2018 Chevy 1500 4x4 with only 1800 mils speed control does not work at highway speeds, only at lower speeds below 40 mph. Once it gets above 40 mph the speed control shuts off, the on light stays on but the speed control will not engage. Once I get below 40 mph the speed control will start working again. 

 

Existing condition of the Truck;

I bought the truck brand new off a Chevy dealer which already had a 6" Pro-Comp Lift and with 35"x 12.5"x 20" tires/rims installed on it.

The Chevy dealer had a company call DSI install all their lifts on their new trucks.

DSI also installed an Hypertech inline speedometer Calibrator.  

I was told that the truck is covered under the chevy standard warranty and DSI covers anything that Chevy will not. [This is also in writing]  

 

After I bought the truck I took it to a local well known 4x4 off road shop and had them replace the stock 3.42 gears with Chevy 4.10 gears.

The truck runs great ! The only issue is that my speed control is not working at highway speeds.

 

I did take the truck to another local Chevy dealer that's closer to where I live, to make a long story short they did try to diagnose the problem but could not find anything. All they could say is that it might have been something to do with the lift kit or the gear change and I should bring it back to the dealer whom I bought it from which I have already schedule an appointment.

 

DSI did remove the Hypertech inline speedometer Calibrator but made no different. 

 

Has anybody else had this issue with there truck? If you have and you had if fixed what was the problem.

 

Thanks,

Dave - 

 

 

Posted
Need Help;
My New 2018 Chevy 1500 4x4 with only 1800 mils speed control does not work at highway speeds, only at lower speeds below 40 mph. Once it gets above 40 mph the speed control shuts off, the on light stays on but the speed control will not engage. Once I get below 40 mph the speed control will start working again. 
 
Existing condition of the Truck;
I bought the truck brand new off a Chevy dealer which already had a 6" Pro-Comp Lift and with 35"x 12.5"x 20" tires/rims installed on it.
The Chevy dealer had a company call DSI install all their lifts on their new trucks.
DSI also installed an Hypertech inline speedometer Calibrator.  
I was told that the truck is covered under the chevy standard warranty and DSI covers anything that Chevy will not. [This is also in writing]  
 
After I bought the truck I took it to a local well known 4x4 off road shop and had them replace the stock 3.42 gears with Chevy 4.10 gears.
The truck runs great ! The only issue is that my speed control is not working at highway speeds.
 
I did take the truck to another local Chevy dealer that's closer to where I live, to make a long story short they did try to diagnose the problem but could not find anything. All they could say is that it might have been something to do with the lift kit or the gear change and I should bring it back to the dealer whom I bought it from which I have already schedule an appointment.
 
DSI did remove the Hypertech inline speedometer Calibrator but made no different. 
 
Has anybody else had this issue with there truck? If you have and you had if fixed what was the problem.
 
Thanks,
Dave - 
 
 

When you say speed control are you talking about cruise control? And did your truck get recalibrated for the new gears?


Sent from above
Posted

The "Speed control" got me. It's like hearing indicator light rather than turn signal. Any hoots I would definitely be taking the truck into the dealer for a checkup.

Posted
On 1/6/2019 at 9:19 PM, TXGREEK said:


When you say speed control are you talking about cruise control? And did your truck get recalibrated for the new gears?


Sent from above

Yes, Cruise Control.

Yes, The original dealer installed a Hypertech inline speedometer Calibrator.  

Posted

They’d installed the Hypertech and then you did the gear swap, right? After the gear swap was the Hypertech adjusted for the lower gearing? 

Posted
On 1/9/2019 at 9:33 AM, AdioSS said:

They’d installed the Hypertech and then you did the gear swap, right? After the gear swap was the Hypertech adjusted for the lower gearing? 

Yes,

I just got it back from the dealer.

The service department told me it's because I installed the 4.10 gears and I was told that they do not not have a program for the 4.10 which is weird because I used stock 410 gears which is available through GMC. So for right now the truck runs great but I do not have cruise control for the highway speeds. Any suggestions? Thanks for your help.

Posted
Yes,
I just got it back from the dealer.
The service department told me it's because I installed the 4.10 gears and I was told that they do not not have a program for the 4.10 which is weird because I used stock 410 gears which is available through GMC. So for right now the truck runs great but I do not have cruise control for the highway speeds. Any suggestions? Thanks for your help.


Get rid of the program period! Redo the truck with a new programmer like SuperChips $320 and start over. Changing out your rear ratio to 4:10 is on the F5. Set to performance and change tire size along with other personal preferences and then the rear end, takes a few minutes.


Sent from above
Posted
3 hours ago, TXGREEK said:

 


Get rid of the program period! Redo the truck with a new programmer like SuperChips $320 and start over. Changing out your rear ratio to 4:10 is on the F5. Set to performance and change tire size along with other personal preferences and then the rear end, takes a few minutes.


Sent from above

 

Bingo

Posted
On 1/11/2019 at 6:41 AM, TXGREEK said:

 


Get rid of the program period! Redo the truck with a new programmer like SuperChips $320 and start over. Changing out your rear ratio to 4:10 is on the F5. Set to performance and change tire size along with other personal preferences and then the rear end, takes a few minutes.


Sent from above

 

Thank you !!!!

Posted
On 1/18/2019 at 3:24 PM, TXGREEK said:

 


Get it done? If not, keep us posted


Sent from above

 

I'm not able to have this programmer sent to me because I'm in California.

I have been looking for a tuner that i'm able to have shipped to me but have not had any luck. 

Any suggestions? 

Posted
I'm not able to have this programmer sent to me because I'm in California.
I have been looking for a tuner that i'm able to have shipped to me but have not had any luck. 
Any suggestions? 

Yes, drive somewhere that does have it and get it done. No one can help you while you live in a socialist state. You can, I’m pretty sure you can order just the calibration unit for gears and tires.


Sent from above
Posted
13 minutes ago, Heritagedave said:

I'm not able to have this programmer sent to me because I'm in California.

I have been looking for a tuner that i'm able to have shipped to me but have not had any luck. 

Any suggestions? 

HP Tuners perhaps.  Can always fine it used pretty easy.  It can do FAR more than any of these other tuners because it is the right way to tune the truck.  It is also the only tuner that can tune your transmission.

Posted
HP Tuners perhaps.  Can always fine it used pretty easy.  It can do FAR more than any of these other tuners because it is the right way to tune the truck.  It is also the only tuner that can tune your transmission.


He’s got a six speed which most of them will do. I’d be cautious buying any used programmer. Some used programmers give to much added headaches and costs in order to recal them if they weren’t done correctly. Lots of used trucks out there being sold with programs still on them leaving the used programmers literally useless


Sent from above
Posted
8 minutes ago, TXGREEK said:

 


He’s got a six speed which most of them will do. I’d be cautious buying any used programmer. Some used programmers give to much added headaches and costs in order to recal them if they weren’t done correctly. Lots of used trucks out there being sold with programs still on them leaving the used programmers literally useless

 

Again, HP Tuners isn't some crappy hand held.  It can tune as many vehicles as you want - you just have to buy the credits.  No issues purchasing a used one.

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