New PCM flash gave me a 7 speed.

[RedundanT]

So last week I took this pile of crap in to get the steering box ordered. While there they decided to flash the PCM. Since then it will hang in 7th till I let off or manually upshift. So glad I bought another jeep. Got the new steering box today, no noticeable difference. Granted I was driving home in gale force winds so I'll hold judgement, but so far it's not looking good.

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[Bingman]

So last week I took this pile of crap in to get the steering box ordered. While there they decided to flash the PCM. Since then it will hang in 7th till I let off or manually upshift. So glad I bought another jeep. Got the new steering box today, no noticeable difference. Granted I was driving home in gale force winds so I'll hold judgement, but so far it's not looking good.

Well that doesn’t sound promising. Mine goes in on the 26th for the new steering box. Before the pcm update, did you ever notice any “spark knock” noise that a lot of people have noticed with the 3.6?

 

[MarkY3130]

I came to this thread hoping you had a manual transmission that magically added a gear. I’d love a 7 speed! (Or an 18 speed with multiple splitters)

 

[zrickety]

So last week I took this pile of crap in to get the steering box ordered. While there they decided to flash the PCM. Since then it will hang in 7th till I let off or manually upshift. So glad I bought another jeep. Got the new steering box today, no noticeable difference. Granted I was driving home in gale force winds so I'll hold judgement, but so far it's not looking good.

You sound pretty angry for a guy that's had the Jeep a month or so? You bought a 2021 or is that sarcasm? I've got a few disappointments with mine but not to this degree.
Have you tried disconnecting the battery? It might help.

 

[RedundanT]

Well that doesn’t sound promising. Mine goes in on the 26th for the new steering box. Before the pcm update, did you ever notice any “spark knock” noise that a lot of people have noticed with the 3.6?

With the 11-1 compression I just ran 91 or better, so never had spark knock.

 

[BrntWS6]

I got the new box and it made a noticeable improvement. Steering is much tighter with less wandering making it easier to drive.

Only thing I had to do is adjust the steering wheel. Tech did not check to see if it was straight when he was done.

 

[zakaron]

I came to this thread hoping you had a manual transmission that magically added a gear. I’d love a 7 speed! (Or an 18 speed with multiple splitters)

That's funny, I was thinking the same! Maybe I could get the flash to turn my manual into a 7 speed. But then I realized that 6th is pretty much useless, so why would I want an extra gear?

 

[Tread4Lo]

Funny you mention that. The Rubicon, even before the steering stabilizer, seemed like it hated 8th gear. NOW, it really hates 8th gear. Running 75mph down the road (and it's pretty flat in Texas), I have to manually shift to 8th.

I think it's a problem with the shift points. Yes, I does seem to have additional spark knock. This last tank was shitty gas, my wife took it to Brookshire's I think. Will never get that again.

 

[RedundanT]

Funny you mention that. The Rubicon, even before the steering stabilizer, seemed like it hated 8th gear. NOW, it really hates 8th gear. Running 75mph down the road (and it's pretty flat in Texas), I have to manually shift to 8th.

I think it's a problem with the shift points. Yes, I does seem to have additional spark knock. This last tank was shitty gas, my wife took it to Brookshire's I think. Will never get that again.

Thanks, glad I'm not the only one that experienced this. I drive the snot out of that 3.6, coming from the Ecoboost 3.5 I want every hamster life there is to give. Never noticed spark knock, but as said earlier, I always used higher octane fuels. Seemed like the MPG was better with it, now I rarely see 18mpg.

 

[Zotch]

Did you verify that the correct parts were installed?

 

[RedundanT]

Did you verify that the correct parts were installed?

Had two tone steering box , now have all black, part number on invoice matches TSB.

 

[BlackGenesis]

Thanks, glad I'm not the only one that experienced this. I drive the snot out of that 3.6, coming from the Ecoboost 3.5 I want every hamster life there is to give. Never noticed spark knock, but as said earlier, I always used higher octane fuels. Seemed like the MPG was better with it, now I rarely see 18mpg.

Lol...hamster powers Jeep.
I have 3.5 EcoBoost in my explorer and love it - this one is tuned on 93 and spin wheels shifting into 2nd. More low end torque then Chevy 6.2L. Power gets addictive and then you miss it in a Jeep.

I bet this flash is to prevent vibration that people have experience at certain speeds.
Vehicle upshifts too high of a gear and drops to very low rpms- 1,600 - 1,800rpms (starts to vibrate).

Maybe new tune (gear upshifst) are baced on load, so it changes all gear upshifst.
Highway - lots of air resistance....

Get Livernois tune they have tune for you engine (pick up up to 50hp with e85, and improved transmission shifting). OEM calibration is junk.

 

[CarbonSteel]

Get Livernois tune they have tune for you engine (puck up up to 50hp with e85, and transmission). OEM calibration is junk.

I did not realize the 3.6L was a flex fuel engine? Of course, then it means MPG will be further reduced by at least 33% of whatever it currently is.

 

[BlackGenesis]

I did not realize the 3.6L was a flex fuel engine? Of course, then it means MPG will be further reduced by at least 33% of whatever it currently is.

It can run flex fuel with tuning.
Mpg on E85 is lower due to lower energy of e85 (car needs to ruch significantly richer 9.8:1 vs 14.7:1).

Nevertheless, its cheaper to run e85 as opposed to premium gasoline. You alsonlookig at up to 15hp extra with e85 vs 93 octane due to how much more timing you can run with very high octane fuel like e85.

It's best to run premium top tier fuel once a month to flush your system regularly and prevent any gumming of injectors with prolong use of e85.

 

[Tread4Lo]

I wouldn't care about the 50hp. It's more about the use of 8th gear. No rattling when the engine is lugged (factory tune lugs the engine).

Hell, my '10 3.8 JK sounded better than this engine. Feel like I'm driving a beater.

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