When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Well I'm confused, GM put a 1L80E in 2014 silverado's!? yep, one gear, 3rd I think. Reverse works and one forward gear.... Other than that it runs like a rapped ape! Looks like I'll be waiting for the BCM to get here next week.
HPTuners has got me perplexed also... on the trans screen there are 2 tabs with a few general boxes, and on the trans diag screen there is nothing... any ideas?
HPTuners has got me perplexed also... on the trans screen there are 2 tabs with a few general boxes, and on the trans diag screen there is nothing... any ideas?
I feel duh - I think I just answered my own question - speedo is reading 158 mph all the time, trans has only one gear, and HPTuners does not have any info in the trans portion of the editor = no serial data connection to the TCM! More to follow....
It sounds like you have a good lead with the trans info not showing up in HPtuners. looking back at the communications diagram, I can't see why a bcm would be needed but I don't have a complete understanding of what info is necessary between all the modules so hopefully it shouldnt be too hard to add the bcm in and see if that solves the issue. Is there still a "low speed" data circuit in these trucks? If so it may be worth looking at or maybe you could post it up.
Other than that the swap looks awesome, real professional. Great job on the power steering solution as well…if those hoses bother you obviously you could just take them to a hose shop and get some crimped up based on what you’ve got there but imo its better to get things up and running and enjoy it and keep the moviation going…can always make things perfect over time
.
Is there still a "low speed" data circuit in these trucks? If so it may be worth looking at or maybe you could post it up.
From what I have seen there is no "Low Speed" data only High Speed. There are 2 circuits that come from the ECM -
High Speed GMLAN Serial Data (+)(3)
High Speed GMLAN Serial Data (-)(3)
High Speed GMLAN Serial Data (+)(1)
High Speed GMLAN Serial Data (-)(1)
In the OBD II data connector there are also 2 circuits - but instead of the (3) circuit there is a (2) circuit. I haven't had the time to go chase this (2) circuit down yet or where the (3) circuit ends (I think it goes to the fuel pump PWM)
High Speed GMLAN Serial Data (+)(1)
High Speed GMLAN Serial Data (-)(1)
High Speed GMLAN Serial Data (+)(2)
High Speed GMLAN Serial Data (-)(2)
Done....I now have a fully functioning 6L80E, and speedometer! One wire, that was all it took! One wire to the trans did not have the correct hookup - keyed instead of constant 12v. Engine runs better now, the throttle response is instant, and 1st gear is almost scary! I'll get some videos posted later this week after I get some things buttoned up on her.
Just a few notes - I did not use a BCM. I found that the only function of the BCM in regards to the trans is a Park/N signal to the starting circuit through the ECM. I did not put the starting circuit through the ECM so no problem there. The only other thing I found was that the BCM does control the charging circuit and alternator. I'm going to bypass this feature.
The High Speed Serial Data (+-) (2) circuit only deals with interior modules that do not affect the engine or trans. So it is not needed in the OBD II connector for this swap.
The High Speed Serial Data (+-) (3) circuit is for the fuel pump and its PWM controller. I bypassed this feature and turned of the DTC's.
I said this before "From what I have seen there is no "Low Speed" data only High Speed". I was wrong, there is a "low speed" data circuit, but is only for interior accessories and is not needed for my swap.
Last edited by GENIIIDude; 01-03-2016 at 10:26 PM.
This thing is full on scary! In first gear it'll lift the front tires of the ground if you stab the throttle! I have to say that in stock form the L83 is a major improvement in power over previous 5.3's, now I'm sure the 4 to 1 first gear of the 6l80 helps too!
great looking tj! I've wanted one since they came out but at this point, I doubt Id find one that wasn't either beat on or about to rust apart. Adding the L83 just makes it that much better.
01-01-2016, 09:12 PM
I feel duh - I think I just answered my own question - speedo is reading 158 mph all the time, trans has only one gear, and HPTuners does not have any info in the trans portion of the editor = no serial data connection to the TCM! More to follow....
awesome work getting that figured out. the fuel pump pwm control sounds like it would be a cool feature to add down the line 
...
