L84 engine & E85

[TRKLGND]

I have a 2020 Trail Boss LT with the L84/10 speed combo.  The L84 is the DFM version of the L83 (AFM).

I have an RPO code of FJW which translates to Gasoline E15.  From that, I am fairly certain the L84 is not E85 compatible.

I'd like to know if anyone has an L84 truck that is E85 compatible from the factory.  Maybe trim levels other than the Trail Boss are.  I doubt it but I am curious.

If not, what is it about DFM that GM would not recommend E85?

I tried chatting on the chevrolet website.  They told me to call the service department for my local dealer.

 

Thanks everyone!
 

[BlancoSilverado]

I was wondering the same thing, so the manual also states E15 max. I believe that our vehicles are not equipped with the ethanol sensor. The L83 are equipped. 

[Black02Silverado]

It is my understanding that the only thing missing is the ethanol sensor.  Don't know if the E85 table is in the ECM like on pre 2019 models since nobody can access it.   Maybe HP Tuners can tell us since they can tune them but you have to send in the ECM and about $2k in funds.

 

Like our 2016 Suburban, it isn't a flex fuel vehicle but I added the sensor.  The plug was under the vehicle right where the sensor would have come from the factory.  Installed the sensor and had Black Bear Performance tune it as well as turn on the E85 table. All is well and more fun to drive now.

 

I did crawl all around under my 2019 and could not find a plug anywhere near the fuel line like I have on our 2016 Suburban.  Bummer in a sense because that means no easy way of adding a sensor.