Forum Discussion
robanddi
May 25, 2015Explorer
Clarification for Dinghy Towing 2015 GMC Yukon Denali XL (Keyless system and no EPB)
When we got our new vehicle we were given supplemental instructions on Dinghy Towing. For our vehicle this supplement replaces pages 10-78 thru 10-79 in the Owner’s Manual. As best as I can determine the only difference has to do with ‘Disconnecting the Towed Vehicle’. Step 5 in the Owner’s Manual indicates Turn the ignition to ON/RUN position with the engine off. In the replacement instructions’ step 5 says Start the engine, then shift the transfer case out of N (Neutral) to Two-Wheel Drive High. See Four-Wheel Drive for directions on shifting out of N (Neutral).
HOWEVER, in the Owner’s Manual on page 9-38 (where our “Shifting Out of N” instructions are located) it indicates the ignition should be in ON/RUN with the engine off! After dinghy towing, should the engine be off or on to shift the transfer case out of N (Neutral)?
****
On our first trial run we were able to shift transfer case into N (Neutral) but were unable to shift the transfer case out of N (Neutral) back to 2WD. After trying to get help unsuccessfully from your Customer Service 800 number, we decided to tow our vehicle to the nearest GMC dealership where finally, on our second trip with vehicle in tow, we were given another set of instructions (#PIP5217A) on how to dinghy tow. These instructions had a revised Step 5.
New Step 5. With the transmission in D (Drive), turn the ignition to ACC/ACCESSORY.
5.1. Shift transmission to P (Park) and turn ignition off.
5.2. Wait 30 seconds before proceeding to the next step.
5.3. Start the engine and shift transmission to D (Drive) verify that the transfer case is still in neutral.
These additional instructions also included how to reset the transfer case error code by removing the 30 amp TREC fuse. The removal and reinstallation of the fuse, allowed us to shift out of N (Neutral) successfully after having gotten the ‘Service 4WD’ message. Furthermore, using the new step 5.2. waiting 30 seconds we were able to shift transfer case into N (Neutral) and then eventually to shift out of N (Neutral) WITHOUT getting the ‘Service 4WD’ message or having to remove the 30 amp fuse.
My husband and I are both disappointed with GM for not providing clear and accurate instructions on dinghy towing. The bulletin #PIP5217A was issued August 21, 2014. We picked up our new car in January 2015! While we were given supplemental towing instructions these did not include the expanded step 5 which apparently is the key to avoiding the transfer case error code. Furthermore, once GM had identified there was an issue with vehicles setting a bogus error code in the transfer case control module, it would make sense to provide owners an update with the expanded instructions, as well as, instructions on how to reset the code or, at the very least, warn them that the ‘Service 4WD’ message and the transfer case stuck in Neutral were related and the error code would need to be cleared before the vehicle would shift from N (Neutral) to 2WD!
Having successfully towed a 2004 4WD Avalanche for years, we are disappointed with the procedure(s) required to tow the Yukon. The complicated and conflicting instructions located in two different sections are irritating. Finally to find out the instructions were not just confusing but incomplete and inadequate was beyond irritating. Our experience with the Customer Service number was inexcusable with the man repeatedly asking me “Why did you put the car in neutral?” This was after I explained exactly what we had done and why! This left us very dissatisfied with your ability to service customers professionally and resolve issues promptly.
While we do understand that not many customers dinghy tow, we specifically ordered this vehicle so we could dinghy tow. I also understand the first supplement applied to multiple vehicles so identifying specific page numbers replaced was not practical; however, it would have been helpful to have a small statement summarizing what steps in the procedure had changed. Then to discover in May 2015 that the supplemental instructions were incorrect and/or incomplete and this was known by GM as early as August 2014 seems inexcusable.
The difficulty in dealing with instructions located in two places in the original Owner’s Manual plus the first supplement and then having to scour around to obtain the final correct information in #PIP5217A has been a huge hassle. AND there is still the unresolved issue of whether the engine should be running or not when attempting to shift the transfer case from N (Neutral) back to 2WD.
It would be really nice to have a complete correct single set of instructions on how to dinghy tow, as well as, to disconnect after flat towing.
Diann
P.S. I am still trying to find a place on GM website to email the above. I refuse to waste a stamp on this! I also have been trying to post on the GMC forum without success. Will try again!
When we got our new vehicle we were given supplemental instructions on Dinghy Towing. For our vehicle this supplement replaces pages 10-78 thru 10-79 in the Owner’s Manual. As best as I can determine the only difference has to do with ‘Disconnecting the Towed Vehicle’. Step 5 in the Owner’s Manual indicates Turn the ignition to ON/RUN position with the engine off. In the replacement instructions’ step 5 says Start the engine, then shift the transfer case out of N (Neutral) to Two-Wheel Drive High. See Four-Wheel Drive for directions on shifting out of N (Neutral).
HOWEVER, in the Owner’s Manual on page 9-38 (where our “Shifting Out of N” instructions are located) it indicates the ignition should be in ON/RUN with the engine off! After dinghy towing, should the engine be off or on to shift the transfer case out of N (Neutral)?
****
On our first trial run we were able to shift transfer case into N (Neutral) but were unable to shift the transfer case out of N (Neutral) back to 2WD. After trying to get help unsuccessfully from your Customer Service 800 number, we decided to tow our vehicle to the nearest GMC dealership where finally, on our second trip with vehicle in tow, we were given another set of instructions (#PIP5217A) on how to dinghy tow. These instructions had a revised Step 5.
New Step 5. With the transmission in D (Drive), turn the ignition to ACC/ACCESSORY.
5.1. Shift transmission to P (Park) and turn ignition off.
5.2. Wait 30 seconds before proceeding to the next step.
5.3. Start the engine and shift transmission to D (Drive) verify that the transfer case is still in neutral.
These additional instructions also included how to reset the transfer case error code by removing the 30 amp TREC fuse. The removal and reinstallation of the fuse, allowed us to shift out of N (Neutral) successfully after having gotten the ‘Service 4WD’ message. Furthermore, using the new step 5.2. waiting 30 seconds we were able to shift transfer case into N (Neutral) and then eventually to shift out of N (Neutral) WITHOUT getting the ‘Service 4WD’ message or having to remove the 30 amp fuse.
My husband and I are both disappointed with GM for not providing clear and accurate instructions on dinghy towing. The bulletin #PIP5217A was issued August 21, 2014. We picked up our new car in January 2015! While we were given supplemental towing instructions these did not include the expanded step 5 which apparently is the key to avoiding the transfer case error code. Furthermore, once GM had identified there was an issue with vehicles setting a bogus error code in the transfer case control module, it would make sense to provide owners an update with the expanded instructions, as well as, instructions on how to reset the code or, at the very least, warn them that the ‘Service 4WD’ message and the transfer case stuck in Neutral were related and the error code would need to be cleared before the vehicle would shift from N (Neutral) to 2WD!
Having successfully towed a 2004 4WD Avalanche for years, we are disappointed with the procedure(s) required to tow the Yukon. The complicated and conflicting instructions located in two different sections are irritating. Finally to find out the instructions were not just confusing but incomplete and inadequate was beyond irritating. Our experience with the Customer Service number was inexcusable with the man repeatedly asking me “Why did you put the car in neutral?” This was after I explained exactly what we had done and why! This left us very dissatisfied with your ability to service customers professionally and resolve issues promptly.
While we do understand that not many customers dinghy tow, we specifically ordered this vehicle so we could dinghy tow. I also understand the first supplement applied to multiple vehicles so identifying specific page numbers replaced was not practical; however, it would have been helpful to have a small statement summarizing what steps in the procedure had changed. Then to discover in May 2015 that the supplemental instructions were incorrect and/or incomplete and this was known by GM as early as August 2014 seems inexcusable.
The difficulty in dealing with instructions located in two places in the original Owner’s Manual plus the first supplement and then having to scour around to obtain the final correct information in #PIP5217A has been a huge hassle. AND there is still the unresolved issue of whether the engine should be running or not when attempting to shift the transfer case from N (Neutral) back to 2WD.
It would be really nice to have a complete correct single set of instructions on how to dinghy tow, as well as, to disconnect after flat towing.
Diann
P.S. I am still trying to find a place on GM website to email the above. I refuse to waste a stamp on this! I also have been trying to post on the GMC forum without success. Will try again!
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