Chrysler 42RE Transmission Controller Brainstorming

Free and Open Source Engine Management discussions excluding more specific things on this board.
thebigmacd
LQFP112 - Up with the play
Posts: 205
Joined: Thu Apr 10, 2008 5:51 pm

Re: Chrysler 42RE Transmission Controller Brainstorming

Post by thebigmacd »

Fred wrote:
thebigmacd wrote:Switching to a 3204 or 3208 in firmware later is beyond trivial (I love SPI/I2C).
Just to clarify, you mean easier than trivial, not harder than trivial, which is how it read to me, right?
For VR I am using LM1815, because once again I have some and I have made them work just fine on a Subaru 6/7 car (probably the only one that actually works from what I can tell).
FYI, the MAX992X is the golden child of VR chips. It is better than LM1815 in virtually every way. The only down side is the SMD nature of it. Saying that only LM1815 ICs work on subby 6/7 is somewhat ridiculous.

Fred.
I know, back from the dead and all, but I did not mean that only LM1815s work with a Subaru, I meant that the specific car was the only Subaru car with LM1815s that works. Pretty much the opposite of what you thought :D
Keith MacDonald
Control Engineering (Systems) Technologist
perlhaqr
TO92 - Vaguely active
Posts: 1
Joined: Tue Oct 07, 2014 2:28 am

Re: Chrysler 42RE Transmission Controller Brainstorming

Post by perlhaqr »

Hey, awesome. I have a bunch of Mopar stuff, all currently running pure hydraulic 3 speed autos (and carbs, and distributors, etc) that I've been contemplating various upgrades to, including OD transmissions. Since getting anything sufficiently new involves electronically controlled transmissions, this is a remarkably fortuitous thread for me to stumble into. :D

Sadly, I'm an utter n00b on this front. I have a huge gap (and, having done a bunch of reading this last weekend, I'm starting to realise that I don't even yet quite grasp just how huge of a gap) in my knowledge, that jumps from "software" (and as y'all might have inferred from the username, not even especially low level software) to "automotive electrical". Where by automotive electrical I mean "actual wires, generally not smaller than 18 gauge, mostly for moving steady state or very slowly switched 12v around, usually to make lights work". My main experiences with "chips" so far to date all also involve salsa. ;)

So, regarding the info posted at the beginning of this thread, is that stuff you figured out from dissecting a 42RE, or is that info you collected from somewhere else? And if you got it from somewhere else, did it have any information as to whether the 727 based transmissions were the same as the 904 based ones? i.e.: does a 47RE have similar values? And thus, would a (custom? homebuilt? See, I don't even know the terminology for this stuff yet. ;) ) controller built to run a 42RE also run a 47RE? Would it at least be adaptable?

-Sandro
RealCuda
TO92 - Vaguely active
Posts: 1
Joined: Tue Mar 03, 2015 7:27 am

Re: Chrysler 42RE Transmission Controller Brainstorming

Post by RealCuda »

Hello I have some questions about the RE transmissions I have a 44RE for a 5.2L Jeep Grand Cherokee and I am wondering if the 1 thru 3 gears are hydraulic or are they some how controlled by the one Solenoid on the governor plate, or is the Shift Solenoid just for 3-4 shifts? sorry to revive this thread but I really have to know to be able to put this trans in my 67 cuda.

Thanks,
RealCuda
baldur
QFP80 - Contributor
Posts: 44
Joined: Tue Aug 19, 2008 4:05 pm

Re: Chrysler 42RE Transmission Controller Brainstorming

Post by baldur »

Bumping an old thread, kudos to you for finding out this information about how that damn governor works.
I have successfully configured an ECU to control a 44RE transmission, without writing a single line of code, just using a mapped general purpose PWM output mapped by road speed and throttle to control the governor and a pair of general purpose switch conditions to control the overdrive and torque converter lock-up.
Post Reply