Yay I broke my transmission.

[kj924]

Oh, one more thing :
The three planetary sets also make available a unique alternate second gear ratio. The primary 2nd gear ratio fits between 1st and 3rd gears for normal through-gear accelerations. The alternate second gear ratio (2nd prime) allows smoother 4-2 kickdowns at high speeds to provide 2nd gear passing performance over a wider highway cruising range.

Hmm, I wonder if your 42RLE can do that

I know my 42RLE doesn't do that...it blows!!

 

[Powerslave]

What? The 45RFE and 545RFE are exactly the same except for software, there was a TSB for the WJs that turns the 45RFE into a 545RFE (it's actually supposed to be 5-45RFE)

http://www.jeepsunlimited.com/forums/showthread.php?t=505893
http://www.wjjeeps.com/tsb/tsb_wj_1802501.pdf

Ones a 4speed, and one is a 5 speed, right? How are they exactly the same. Just going by your initial 545(RFE) and 45(RFE) being the SAME reference, the 5 in front of the other 45, is a 5-speed, not a 4 speed... just saying...

The 42RLE and 45RFE are both 4-speeds, your post had 545 in it, the leading 5 indicates the 5-speed... The 45RFE has all the other internal goodies the 42RLE does not, but the 545RFE is a 5-speed! Also, On the 45 and 545RFE the design provides you with 2nd, and 3rd gear, based on the shift lever position, in case an electronic control system failure occurs; limp-mode. That's nice too, instead of being stuck in 2nd all the time with the 42RLE.

Yes, I mentioned the spin on filter, that is for the return path.

I know about the three planetary gear set, and that 2nd gear, called 2nd prime (for down-shfting), with a 1.50:1 ratio -vs- the 2nd gear 1.67:1 ratio.

How about a 68RFE? That won't fit, huh?

This gets all confusing, doesn't it?

 

[kj924]

(dunno)

 

[JeepJeepster]

Ones a 4speed, and one is a 5 speed, right? How are they exactly the same. Just going by your initial 545(RFE) and 45(RFE) being the SAME reference, the 5 in front of the other 45, is a 5-speed, not a 4 speed... just saying...

The 42RLE and 45RFE are both 4-speeds, your post had 545 in it, the leading 5 indicates the 5-speed... The 45RFE has all the other internal goodies the 42RLE does not, but the 545RFE is a 5-speed! Also, On the 45 and 545RFE the design provides you with 2nd, and 3rd gear, based on the shift lever position, in case an electronic control system failure occurs; limp-mode. That's nice too, instead of being stuck in 2nd all the time with the 42RLE.

Yes, I mentioned the spin on filter, that is for the return path.

I know about the three planetary gear set, and that 2nd gear, called 2nd prime (for down-shfting), with a 1.50:1 ratio -vs- the 2nd gear 1.67:1 ratio.

How about a 68RFE? That won't fit, huh?

This gets all confusing, doesn't it?

Its all about the gearing. Its possible to have more than 4 forward gears the way the gearing is set up in the 45rfe. Wonder how many R gears you can get.. 3?

 

[sleeve]

Ones a 4speed, and one is a 5 speed, right? How are they exactly the same. Just going by your initial 545(RFE) and 45(RFE) being the SAME reference, the 5 in front of the other 45, is a 5-speed, not a 4 speed... just saying...

While they might not be "exactly" the same in terms of naming, both transmissions are nearly identical on the inside.

Wiki on 45RFE & 545RFE it's a good read BTW.

A guy on lost took his 45RFE and reprogrammed it to act like a 545RFE. [The forum is currently down so I can't hot link to the thread though]

 

[LibertyOrDeath]

45RFE: has two overdrive ratios and uses 4 ratios in its normal shift sequence. See the last part of the article at this page.

The 45RFE transmission

RFE stands for rear wheel drive, fully electronic. This is an electronically-controlled transmission with five forward ratios including an alternate second gear ratio for improved performance for passing and better fuel economy. It was designed for Jeeps but was used later in Dodge trucks; its first use was in the 1999 Grand Cherokee V8.

The transmission features a tall, 3.00:1 first gear that gives the driver better initial acceleration. Real-time driver adaptive shifting fine-tunes the shift pattern to the driver, while an alternate second gear ratio gives the driver five forward ratios. During acceleration, second gear has a ratio of 1.67. Depending on speed and throttle position, both this gear and an alternate 1.50 second gear ratio are available for kick-down operation, making the down-shift smoother. Its reverse gear ratio is equal to the first gear ratio, to allow for heavier loads.

Other features include three planetary gear sets that combine the widest range of gear ratios available in any transmission in its class. Combined with precise step selections, this brings smooth shifts and maximum power and optimal fuel economy.

The transmission is built at the Indiana Transmission Plant in Kokomo, Indiana, in an all-new 1.2-million square-foot facility.

545RFE: has two overdrive ratios and uses 5 ratios in its normal shift sequence. When you floor the throttle at highway speeds it will downshift to the taller numerical second gear ratio to help smooth out the downshift. Starting in 2009, the 545RFE allowed drivers to select the highest gear the transmission would shift to (for towing, hill climbing, and hill descent).

(dunno)

 

[trail rated]

Ones a 4speed, and one is a 5 speed, right? How are they exactly the same. Just going by your initial 545(RFE) and 45(RFE) being the SAME reference, the 5 in front of the other 45, is a 5-speed, not a 4 speed... just saying...

The 42RLE and 45RFE are both 4-speeds, your post had 545 in it, the leading 5 indicates the 5-speed... The 45RFE has all the other internal goodies the 42RLE does not, but the 545RFE is a 5-speed! Also, On the 45 and 545RFE the design provides you with 2nd, and 3rd gear, based on the shift lever position, in case an electronic control system failure occurs; limp-mode. That's nice too, instead of being stuck in 2nd all the time with the 42RLE.

Yes, I mentioned the spin on filter, that is for the return path.

I know about the three planetary gear set, and that 2nd gear, called 2nd prime (for down-shfting), with a 1.50:1 ratio -vs- the 2nd gear 1.67:1 ratio.

How about a 68RFE? That won't fit, huh?

This gets all confusing, doesn't it?

Right, they are both exactly the same mechanically, except for the TCM programing.

Maybe we didn't understand each other. This are quotes from your post:

You mean the 42RLE and 45RFE are the same besides programming...

No, the 42RLE is not the same as the 45RFE.

The other has a whole other gear, like totally...

5th Gear ratio - 0.67 : 1

The 45RFE is still capable of the 5th gear; the only difference is programing.

 

[kj924]

(popcorn)

 

[Marlon_JB2]

No, no, no.... the 545RFE and 45RFE are (NOT) the same.

One has 4 gears (45RFE), one has 5 gears (545RFE).

You can flash a 45RFE to THINK it is a 545RFE, but it is STILL missing a gear.

 

[ThunderbirdJunkie]

It's only missing it in programming, it's not physically MISSING the gear

 

[Powerslave]

It's only missing it in programming, it's not physically MISSING the gear

So, you are saying the GUTS are in there, but the car doesn't know it has it? That seemed a little far fetched. but:

http://www.scribd.com/doc/7095618/545rfe-Transmission-Manual

Ok so that manual says it is for both them... Yeah, that is confusing, but I see the manual has both models listed. You can see the chart on page four to see how fifth gear is achieved (OD & 2C)for the 545RFE, with the same clutches as the 45RFE. Still, there has to be some reason, besides programming, you can't get 5th gear, unless the 45RFE doesn't have the same valve body, something?

Strange, but yeah, it's true, they seem to be the same hardware wise...

 

[ThunderbirdJunkie]

Wow. Didn't know that...

 

[Powerslave]

Yeah, it is not actually an additional clutch for the gear, it is using the OD and 2C clutches for 5th gear. You can see the clutches in both charts, they are the same; and only 5th gear has a different clutch engagement pattern. It can be as simple just a program change but, or even TCM; but you also need the shifter, and that is even if the 45RFE allows all the positions, and 5th is not physically locked out at the spline where the shift cable hooks up to...

 

[trail rated]

Yeah, it is not actually an additional clutch for the gear, it is using the OD and 2C clutches for 5th gear. You can see the clutches in both charts, they are the same; and only 5th gear has a different clutch engagement pattern. It can be as simple just a program change but, or even TCM; but you also need the shifter, and that is even if the 45RFE allows all the positions, and 5th is not physically locked out at the spline where the shift cable hooks up to...

Shift cable??? The shifter positions are the same for the 45RFE and 545RFE (1st, 2nd, [D]), you can not 'tell' the 545RFE to go into 4th by just moving a lever or pushing a button. The TCM controls that.

Simply put, the 45RFE and 545RFE are EXACTLY the same mechanically, same TCM (computer), same shifter, same EVERYTHING. The only difference is TCM programing (software). Stop thinking that the 45RFE and 545RFE are different transmissions, they are not!

Like I said before, the 45RFE is capable of 9 forward gears and 3 reverse. However, the computer is programed to only use 4 forward gears.

 

[JeepJeepster]

Shift cable??? The shifter positions are the same for the 45RFE and 545RFE (1st, 2nd, [D]), you can not 'tell' the 545RFE to go into 4th by just moving a lever or pushing a button. The TCM controls that.

Simply put, the 45RFE and 545RFE are EXACTLY the same mechanically, same TCM (computer), same shifter, same EVERYTHING. The only difference is TCM programing (software). Stop thinking that the 45RFE and 545RFE are different transmissions, they are not!

Like I said before, the 45RFE is capable of 9 forward gears and 3 reverse. However, the computer is programed to only use 4 forward gears.

Thought I had read that it can have 3 R gears. That would be pretty sweet.

 

[ThunderbirdJunkie]

ThunderbirdJunkie wonders who can flash it to use 9 forward gears...and potentially an electronic control to manually select any one of them

That would be wicked snazzy

 

[tjkj2002]

No, no, no.... the 545RFE and 45RFE are (NOT) the same.

One has 5 gears (45RFE), one has 6 gears (545RFE).

Fixed it for you...............

Simply put, the 45RFE and 545RFE are EXACTLY the same mechanically, same TCM (computer), same shifter, same EVERYTHING. The only difference is TCM programing (software). Stop thinking that the 45RFE and 545RFE are different transmissions, they are not!

Actually the internal parts are different(check the part #'s),case is the same though.

 

[trail rated]

Actually the internal parts are different(check the part #'s),case is the same though.

Yes, some of the parts were updated but they function the same.

 

[Marlon_JB2]

Fixed it for you...............

Actually the internal parts are different(check the part #'s),case is the same though.

Oops. I knew that.

And thankfully, finally someone else knows these two transmissions are not exactly the same!

 

[trail rated]

And thankfully, finally someone else knows these two transmissions are not exactly the same!

](*,)

You know what, I give up.