42RLE transmission reprogram/shift kit??

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loves_off_roading

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My 42RLE has worked fine. But I always have to turn the overdrive off going up big hills to give it more power. It's annoying but I've been able to deal with it. Wish mine had the 45 tho I hear it's a lot tougher.
 

J-Thompson

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yeah, that does work...i was just looking for a more permanent improvement.


what you want it a rig that will drive it self for you
the driving is your job
I have NO issues going up hills with 3.5 people ,.5 = a 2 year old, a weeks worth of crap including some on the roof causing wind drag
yeah it starts to slow from 65 then I keep pushing the gas and bam down shift
and up it goes
oh and I was doing this with 245/75 MTR's and 3.73's

put in 4.10's that will help but at a cost
or just push the freaking gas
 

Ry' N Jen

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Never been a problem for us either!
The only time Jen and I use overdrive is on long flat land Highway/Interstate runs.
When we're traveling North or East in mountainous terrain, the O/D gets turned off and the automatic transmission gets shifted manually as well.
 

osufans

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what you want it a rig that will drive it self for you
the driving is your job
I have NO issues going up hills with 3.5 people ,.5 = a 2 year old, a weeks worth of crap including some on the roof causing wind drag
yeah it starts to slow from 65 then I keep pushing the gas and bam down shift
and up it goes
oh and I was doing this with 245/75 MTR's and 3.73's

put in 4.10's that will help but at a cost
or just push the freaking gas

well....it is called an AUTOMATIC transmission! lol

if i wanted to do manual shifting, i'd have bought one with a manual transmission. nuff said! :)

in all seriousness though, go drive a Chrysler T&C (Gen 4 anyways, not sure about the new ones) and tell me how much better the shift points and converter lockup match the torque of the motor. that's my only bugger about this Libby. i'm just comparing it to what i know.
 

KYLiberty

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well....it is called an AUTOMATIC transmission! lol

if i wanted to do manual shifting, i'd have bought one with a manual transmission. nuff said! :)

in all seriousness though, go drive a Chrysler T&C (Gen 4 anyways, not sure about the new ones) and tell me how much better the shift points and converter lockup match the torque of the motor. that's my only bugger about this Libby. i'm just comparing it to what i know.

You might want to consider what he's driving through. Mountains in BC in winter without manually shifting in areas...No thanks. I manually shifted mine some of the way home today. When conditions are like they are right now and I'm going through these hilly side streets that don't get plowed, salted, or anything it really helps.

Since the computer is altogether on most 42rles cant they do everything at the same time? They stopped using separate computers in 2003 sometime.

They can. They just have the transmission flash listed separately on their site. If you are serious about changing the way your KJ drives, I would highly recommend starting with B&G. Then continue making upgrades as needed or desired until you're happy. It's a good place to start. It doesn't cost too much in the grand scheme of things, and is very easy to do yourself so you don't need to pay for labor.
 

jafstl38

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Thats what i have been doing for 5 years, its not really a work around, it works, I run mine till I hit 87 then kick it in to OD!

I have this same issue except i always turn my O/D off on the highway! otherwise it will just sit at 65-70mph at 1900rpms and not want to go anywhere! Ive gone up a hill at 75mph and reached the top at 50!? Its pretty pathetic it cant even get out of its own way!? I really wish there was a fix for this, is there a way to tell if your TCM has been re-flashed for the "improved hill-climb flash"? I bought mine used and its a 04 so I have no idea if it has been ever performed.:shrug:
 

LibertyOrDeath

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The 42RLE has crap gear ratios,add a lack luster torque curve of the 3.7 = piss poor driveability and prone to overheating.

There is no fix,the "shift kit" for the 42RLE is useless and does not do much,changing the shift points will not help either since you still have crap ratio's.


Long live the '02 KJ's with the 45RFE(woot)

Not to mention it doesn't take much abuse in reverse.
 

Doublecardan

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Great Discussion, I am glad I am not the only one to notice the dramatic dropoff between OD and 3rd. I wonder though, does the Diesel have the same issues or even the same ******?
 

resistance

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This was what I have been trying to find out for some time. I was thinking this was some kind of power loss caused by larger tires, old spark plugs, air filter, intake system or anything else. I was sorry to learn that nothing was actually wrong, it was only the 42RLE:(

Pathetic performance for a 3.7 V6, especially when driving uphill or when you need instant acceleleration. It feels like driving a fully loaded 1.6 four ****** sometimes:( This is not the real potential of this engine.

I e-mailed B&G for a PCM flash, but no reply yet. Still looking for other solutions..
 

J-Thompson

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This was what I have been trying to find out for some time. I was thinking this was some kind of power loss caused by larger tires, old spark plugs, air filter, intake system or anything else. I was sorry to learn that nothing was actually wrong, it was only the 42RLE:(

Pathetic performance for a 3.7 V6, especially when driving uphill or when you need instant acceleleration. It feels like driving a fully loaded 1.6 four ****** sometimes:( This is not the real potential of this engine.

I e-mailed B&G for a PCM flash, but no reply yet. Still looking for other solutions..


Why are you blaming the engine for the down fall of the transmission
the issue with the trans is gearing
first gear and reverse are both to tall ,numerically small
the shift into O/D early is electronics or drivers not wanting to hit the gas
I never had shift issues ,but I had the 45RFE
I also never had a problem with hitting the gas
 

Bullett55

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CRD has the 545rfe transmission I have it in my commander much better than the 42rle. I can back up a steep hill with it.

Yeah..., try backing your single jet ski trailer (ttl wt less than 1100 lb) up even a modestly inclined driveway!! Just got my Rennie (42RLE w/69M) back from dealer trans rebuild. I still love it... but Jeeez......!
 

Marlon_JB2

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Good god if you guys think the 3.7L/42RLE/3.73 gearing is bad, you REALLY need to try a WK 3.7L/W5A580/3.07 combo.

Long live the 42RLE. :)
 

desync0

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Not that I'm sure if it's ever been done, or even compatible, but I'd put a 545RFE in before I'd put in a 45RFE!!! lol


Just and FYI they're the same ******, just different programming.

45rfe dodge ram's can swap out for a grand cherokee ECM and pick up the 5th gear.

And there's actually 6 forward gears, but it's programed as 5, with a 2nd, 2nd gear that's only used on down shift/heavy acceleration.
 

resistance

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Why are you blaming the engine for the down fall of the transmission

I'm not blaming the engine. I say that despite the strong engine, the overall performance is poor. No matter if I switch the OD off, hit the gas or keep it in the 2nd gear, the acceleration is interrupted by auto shifting again.

B&G don't seem to respond, and even if they do, international shipping will be another issue. Isn't there any other way to get better PCM programming?
 

J-Thompson

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I'm not blaming the engine. I say that despite the strong engine, the overall performance is poor. No matter if I switch the OD off, hit the gas or keep it in the 2nd gear, the acceleration is interrupted by auto shifting again.

B&G don't seem to respond, and even if they do, international shipping will be another issue. Isn't there any other way to get better PCM programming?


so let me make sure I understand what you are saying
if you are going 55 mph and press the gas ALL THE WAY TO THE FLOOR
it does not down shift and go ,quickly?
if not then there is a problem besides the "lack luster" transmission
also if you shift the gear selector into second it does not stay in second
it should ONLY shift 1>2 and hold ,I think but it may stay in second only

let me say this
if you are truly hitting the gas and getting 4500 or more RPM but still do not have "giddy up" then you have another problem
if you are not hitting the 4500 RPM range then you are not really hitting the gas
 

tjkj2002

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Somewhere between being sane and insane!
so let me make sure I understand what you are saying
if you are going 55 mph and press the gas ALL THE WAY TO THE FLOOR
it does not down shift and go ,quickly?
if not then there is a problem besides the "lack luster" transmission
also if you shift the gear selector into second it does not stay in second
it should ONLY shift 1>2 and hold ,I think but it may stay in second only

let me say this
if you are truly hitting the gas and getting 4500 or more RPM but still do not have "giddy up" then you have another problem
if you are not hitting the 4500 RPM range then you are not really hitting the gas
I'm agreeing.....................

If your not jumping to well over 4500rpm's when you floor it at speeds over 55mph+ you got other issues that need to be fixed first.I know in my KJ(before SFA) with the 45RFE I would be pushing 5000rpm's at 50-55mph in 2nd-prime which is close to the 42RLE's 2nd.
 
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