Rpo Code Concern

scuba steve · January 23, 2008

My 5.3 litre has a engine rpo code of l59.based on the rpo search engine on this site it could be one of six different 5.3 litres listed. some of which are flex fuel and some that arent . how can i tell if my engine is flex fuel or not? and also i was told over the phone while confirming my warranty thru gm that there was an open recall on my vin that had to do with a reprogramming of my pcm and tcm , has anyone had this recall done and if so what was the difference afterwards?i was told i had till 80,000 miles to have it done but that it was not 100% neccesary.

jrrod2004 · January 23, 2008

Vin?

MS3DALE · January 23, 2008

RPO code "L59" is the Flex-Fuel 5.3 V8.

GM is installing Yellow gas caps on vehicles that can run on E85 "Flex-Fuel",But '06 was probably too early for yours to get the Yellow gas cap.

And Yes,Most '06-'07 "Classic" trucks with the L59 engine did have a recall for reprogramming.

I would get it done.

Lahatiel · January 23, 2008

On a side note, what is the significance of the L33 5.3 engine? (sorry if I appear to be hijacking).

MS3DALE · January 23, 2008

The "L33" is a "H.O." Aluminum Block 5.3 thats rated for 310 HP. It CANNOT run E85 "Flex-Fuel".

The "L59" (Along with the LM7) is an iron block 5.3.

scuba steve · January 24, 2008

RPO code "L59" is the Flex-Fuel 5.3 V8.

GM is installing Yellow gas caps on vehicles that can run on E85 "Flex-Fuel",But '06 was probably too early for yours to get the Yellow gas cap.

And Yes,Most '06-'07 "Classic" trucks with the L59 engine did have a recall for reprogramming.

I would get it done.

what is it that makes my truck a classic?

scuba steve · January 24, 2008

oh yeah and im also curious about how to tell if my motor is equipped with the cylinder deactivation program. ive read a little about that and i know it was available in my year but not quite sure if my truck does have it.

ridnlow · January 24, 2008

RPO code "L59" is the Flex-Fuel 5.3 V8.

GM is installing Yellow gas caps on vehicles that can run on E85 "Flex-Fuel",But '06 was probably too early for yours to get the Yellow gas cap.

And Yes,Most '06-'07 "Classic" trucks with the L59 engine did have a recall for reprogramming.

I would get it done.

what is it that makes my truck a classic?

Classic trucks are the GMT-800 trucks, the body style right before the current one..

alaska511 · January 24, 2008

oh yeah and im also curious about how to tell if my motor is equipped with the cylinder deactivation program. ive read a little about that and i know it was available in my year but not quite sure if my truck does have it.

I thought LH6 was the RPO for 5.3 HO w/ Cylinder Deactivation ?? I could be wrong...anybody ??

MS3DALE · January 24, 2008

oh yeah and im also curious about how to tell if my motor is equipped with the cylinder deactivation program. ive read a little about that and i know it was available in my year but not quite sure if my truck does have it.

No,Your truck does not have the cylinder deactivation,or "AFM" (Active Fuel Management)

None of the GMT800 trucks have it.

MS3DALE · January 24, 2008

oh yeah and im also curious about how to tell if my motor is equipped with the cylinder deactivation program. ive read a little about that and i know it was available in my year but not quite sure if my truck does have it.

I thought LH6 was the RPO for 5.3 HO w/ Cylinder Deactivation ?? I could be wrong...anybody ??

LH6 is the code for the aluminum block 5.3 with AFM,LY5 is the code for the iron block 5.3 with AFM.

These are for the NBS GMT900 trucks,Neither one are considered "HO".