I put a 2018 6speed manual trans in my 2015 mustang gt

[Ryanbeers]

Is there anything else I have to do electrical wise because I no the 18 revs on its own when u downshift since I swapped I have had multiple mis fires so I did a crank relearn now it still runs like crap everyonce in a while I'll get some power outta it but usually like 1st and 4 th gear other then that it's like the dead zone check engine light came on and it said intake runner stuck is it considental that it happen same time I changed tranny?

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[Dinokill3.7]

Isn’t the 18s MT82 pretty weak compared with the previous years? There were a lot of people blowing up 18s transmissions

 

[Zrussian13]

18s don't have rev match. That started in 19. And yes the shift forks were poorly designed. That changed at some point in 19 I believe.

 

[boB]

We know that rev-match started with 2019. What we don't know is if the 2018 transmissions have the gear select sensor that enables rev-match. Look way up high on the left side of your transmission: if it has a black box with a 6 pin connector then it has the sensor. If so then you are boned because your car does not have the wires to go to that connector nor does the transmission have the sensors your car requires.

If your transmission does not have the black box then there is probably something else wrong.

 

[Cobra Jet]

Intake runner issue isn't going to be a trans issue, that's most likely the common failed IMRC issue and most likely coincidence that you're getting the code after a trans swap.

The IMRC failure is occurring with the actuator rod that is integral to the intake. The rod snaps, which renders the actuation of the IMRC plates useless and in-op.

Check this thread and Post #15 for the picture of what I am referencing:

https://www.mustang6g.com/forums/threads/our-first-dtc-p0308.160243/

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You could have a VCT issue as well; here's this thread regarding VCT issues:
https://www.mustang6g.com/forums/threads/chirp-cricket-noise-at-warm-idle.148456/#post-3169442

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Check over your work and make sure no harnesses are damaged and any connectars are secure. the crank relearn again too, sometimes the first go around may not have worked.

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Extract codes because having actual codes is most helpful when posting about XYZ issues for folks to be able to better assist.

 

[ice445]

We know that rev-match started with 2019. What we don't know is if the 2018 transmissions have the gear select sensor that enables rev-match. Look way up high on the left side of your transmission: if it has a black box with a 6 pin connector then it has the sensor. If so then you are boned because your car does not have the wires to go to that connector nor does the transmission have the sensors your car requires.

If your transmission does not have the black box then there is probably something else wrong.

It shouldn't matter, if the car doesn't have the active rev match on the software side it won't even be looking for that trans sensor luckily.

 

[Ryanbeers]

Thank u for the reply well I thought it was the intake the lmrc we're sticking .....so I bought a 21 intake manifold did the lockouts and car still runs the same so what it's doing is first gear will almost rev out then it hits a flat spot no power then second is good to about 3 k rpm then flat spot shift to 3 rd gear same thing then 4th gear will rev out almost all the way then usually the same as 2&3 gear and 6 will rev out ¿???????I have done a crank relearn because I have misfires so no more mis fire but no more power either ...this all happened to at the same time I put the 18 6 speed manual trans in I had to change the flywheel because it's a dual clutch set up and that's it I'm super stumped any help would be nice .

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[Hi-PO Stang]

One thing about the good ole days was you could buy an trans adapter and put any trans in your car. I would think you could find a Ford certified mechanic that could help out with the problem after the trans swap. Maybe the Ford tech could do some electronic analysis at the dealership.

 

[GregO]

so what it's doing is first gear will almost rev out then it hits a flat spot no power then second is good to about 3 k rpm then flat spot shift to 3 rd gear same thing then 4th gear will rev out almost all the way then usually the same as 2&3 gear and 6 will rev out ¿???????I

I think the issue is the difference between 2011-17 and 2018-up transmission gear ratios. The ratio difference is causing Fords Torque based programing communication issues with drive by wire throttle settings. This could cause a host of engine management issue along with the IMRC code you mentioned.

I'm just a laymen here, is there's merit in asking a tuning professional if the speed tables need revisions for the 2018 gear ratios ? Search TREMEC conversion and you'll see a few returned back to the MT82.

Judging by the ratios below I can see why you're experiencing power cutoff at every gear but 4th and 6th if this a speed sensor programming issue. You stated that 4th will rev out. The 2018 trans 4th gear is 1:1 where as 2011-17 5th is 1:1. 6th gear is only .028:1 different which probably is about the same ratio difference as new tires vs. used tires down to the wear bars.

Thanks to STEEDA for publishing the table below.

 

[mech94]

make sure you didn't pinch the wiring harness between the block and transmission

 

[Ryanbeers]

I think the issue is the difference between 2011-17 and 2018-up transmission gear ratios. The ratio difference is causing Fords Torque based programing communication issues with drive by wire throttle settings. This could cause a host of engine management issue along with the IMRC code you mentioned.

I'm just a laymen here, is there's merit in asking a tuning professional if the speed tables need revisions for the 2018 gear ratios ? Search TREMEC conversion and you'll see a few returned back to the MT82.

Judging by the ratios below I can see why you're experiencing power cutoff at every gear but 4th and 6th if this a speed sensor programming issue. You stated that 4th will rev out. The 2018 trans 4th gear is 1:1 where as 2011-17 5th is 1:1. 6th gear is only .028:1 different which probably is about the same ratio difference as new tires vs. used tires down to the wear bars.

Thank you that totally makes sense wonder what to do about that could I get a 18 speed sensor

 

[GregO]

Thank you that totally makes sense wonder what to do about that could I get a 18 speed sensor

Ford OEM transmission speed sensor looks to be the same from 2011-2020.

I'm not 100% but this probably is programming related.

Another thought, 2015-17 use an ABS sensor to measure speed along with a transmission output shaft speed sensor. I keep gravitating to the ratio difference causing your issues.

 

[boB]

At this point you need the electrical diagrams for 2015 and 2018 to see what is different.

 

[GregO]

@Ryanbeers
Did you get all the issues sorted out ?

 

[Ryanbeers]

No I didn't still runs like shit did find out I didn't plug one of the o2 sensors all the way so now it is but still didn't change anything still cuts out anything ubove 3 thousand rpm in all the gears insept for 4 gear it has no power

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