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ChevyTech · 02-12-2019, 04:53 PM

There is no engine or transmission information so I can't answer some questions you sent me in the private message.

1994 pickups with automatic transmissions were electronically shifted by the computer. The only 1991 trucks that were electronically shifted were the big blocks that had the 4L80E transmission. A 1994 with an automatic transmission has an 8192 baud rate PCM. A 1991 pickup without a big block using a 4L80E would have a 160 Baud rate C3 ECM. There are very big differences in the wiring between these two vehicles.

Can a 1994 instrument panel be put in a 1991? - Yes but it will take a bit of work.

In 1991 the DRAC module was built into the instrument cluster. In 1994 the DRAC module was separate from the instrument panel assembly.

To put a 1994 instrument panel in a 1991 you are going to have to wire in a DRAC module to make it work. You will need the instrument panel connector from a 1994. You will have to recalibrate the DRAC module for your truck.

02-12-2019, 04:53 PM	#7
ChevyTech Registered User Join Date: May 2004 Location: Minnesota Posts: 4,620	Re: 91 non tach/ 94 tach There is no engine or transmission information so I can't answer some questions you sent me in the private message. 1994 pickups with automatic transmissions were electronically shifted by the computer. The only 1991 trucks that were electronically shifted were the big blocks that had the 4L80E transmission. A 1994 with an automatic transmission has an 8192 baud rate PCM. A 1991 pickup without a big block using a 4L80E would have a 160 Baud rate C3 ECM. There are very big differences in the wiring between these two vehicles. Can a 1994 instrument panel be put in a 1991? - Yes but it will take a bit of work. In 1991 the DRAC module was built into the instrument cluster. In 1994 the DRAC module was separate from the instrument panel assembly. To put a 1994 instrument panel in a 1991 you are going to have to wire in a DRAC module to make it work. You will need the instrument panel connector from a 1994. You will have to recalibrate the DRAC module for your truck. __________________ For those of you that are wondering why you are not getting replies to your thread: Did you give the model, year, engine, fuel system type, and transmission information? If it is modified from what came stock from the factory, let us know that too.