Reprogramming GM Vehicles Not Using TIS2Web
I've got a fleet customer that is an independent contractor for FedEx. He owns 10 GMC Savana G-3500's that are box trucks. These vehicles originally started life as Penske and U-Haul rentals. The newer ones - 14 on up, default to have the tow switch being on with every key cycle, and there is no message to change the oil and no oil life remaining displayed on the DIC.
He said his drivers forget to press the switch off (which affects gas mileage) and this vehicle didn't have the oil changed for a long time because there was no reminder to change the oil.
In the past I've called AC Delco and have had changes made before that were factory options. They don't call them VCI's anymore, but...I've placed a call and they say they won't do this, even though it sounded like they have in the past?
The owner would like to have these changes made and was willing to pay for it, but AC Delco said it's not possible anymore. Are there aftermarket programming options available? I'm thinking for the tow/haul the TCM would have to be programmed, and for the oil life monitoring the IPC. My thoughts are most of the aftermarket programmers are performance oriented and not really designed for changing settings that most of the vehicles already had, but were requested by Penske...
Hi Scott, HP Tuners and EFI Live are both options that may have a switch for the tow issue. You would have to pull the tune and look at it to see if either company added the switch in the software. For the oil minder I am not aware of any aftermarket solutions. If the transmissions are Allison then it is possible you may be able to use Allison software with a pass-through like Nexiq.
Hi Michael, I appreciate the reply. I’ve got a friend that does custom tunes and he uses HP Tuner. I gave him a call and he said the TCM might be doable, but the OLM he doesn’t think so…It looks like GM/AC Delco has someone on this site and I’ll post an update. Thank you,
If I am around a similar vehicle tomorrow I will read the ECM and TCM with HP tuners and see what options are available. If I find something out I will report back.
Hi Benjamin, It looks like it might be taken care of. See my update. Thanks for the response.
With all due respect to DN. This sounded very familiar to me. members.iatn.net/forums/read/ms…; The work-around wiring diagram that Dustin Lof provided is found here: members.iatn.net/file/view/?id…; If the links aren't legal I hope the admins pull this post and let me know so.
Hi Jaime, That was what was strange about this was I already prepared the customer for a charge and GM/AC Delco said they’ve done this in the past. Looking at RPO’s Penske had these special options - 5F2 : CALIBRATION SUPPRESSION, ENG OIL CHANGE IND 5G8 : CALIBRATION - ACTIVATION 'ON' I’m not sure why they requested to remove the OLM other than they just used mileage. I’ve had other vehicles…
So I am guessing the RPO 5F2 is why the OLM does not display ...Interesting
Hi Glen, You're right about the 5F2. I'm having a hard time understanding why they would remove the OLM other than they didn't want people playing with the DIC and then they never changed the oil? Thank you,
Hi Scott: I can't speak for Penske but when I was a Ryder, ANYTHING that could possibly construed as encouraging the driver to do anything but drive was removed from the unit during the Inservice. The reason was liability, perceived and real. This included jacks, lug wrenches, spare tires and even Owner's Manuals. They got fusees (replaced by triangles) and fire extinguishers. (Fuse boxes had…
You would have MY vote (if I were a one-topic voter, and this was my priority). < grin >
Evidently GM/AC Delco, (or someone connected, Lance?) monitors these forums as I received a call this morning from AC Delco. She said they would change the calibration file for this vehicle to have the Tow/Haul default to off. I asked about the OLM and she wasn’t sure about that. I think I’ll email them and see if we can get the 5F2 changed as well before I have the customer come in. They have 4…
Well, that's easier than making and installing a circuit to do what a simple software change can! Do you know whether it will require you to use a special method (read: VCI) method or will it be a part of a "regular" flash?
Hi Jaime, So, yes it is easier than coming up with creative methods as a workaround method, but it turned into a little bit more. Because there are multiple modules involved with this, I wanted to make sure the vehicle was going to work as I/He wants it to. When I initially heard that AC Delco was going to do this I was told the cost involved was $100. I told them to do it, but I wanted to…