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-   -   545rfe reliability/durability (2010) (http://www.jeepgarage.org/f5/545rfe-reliability-durability-2010-a-72290.html)

Unobtanium 03-01-2014 02:23 AM

545rfe reliability/durability (2010)
 
How durable/reliable is my transmission? I have a bad history with slushboxes...never owned a mopar though...

Strongjeff 03-01-2014 02:26 AM

Re: 545rfe reliability/durability (2010)
 
Quote:

Originally Posted by Unobtanium (Post 984308)
How durable/reliable is my transmission? I have a bad history with slushboxes...never owned a mopar though...

it's a fairly reliable transmission, although it can stand to be tuned for better performance. its good to around 400-450 horsepower before you would need to upgrade it. just do your normal maintenance on it and you should be fine as long as you own it.

Unobtanium 03-01-2014 02:29 AM

Re: 545rfe reliability/durability (2010)
 
Quote:

Originally Posted by Strongjeff (Post 984311)
it's a fairly reliable transmission, although it can stand to be tuned for better performance. its good to around 400-450 horsepower before you would need to upgrade it. just do your normal maintenance on it and you should be fine as long as you own it.

I'm staying stock 357/389. If I wanted more I'd go srt8. My fear was than 2nd prime. I've heard flooring it from a roll is a nono?

Strongjeff 03-01-2014 02:32 AM

Re: 545rfe reliability/durability (2010)
 
Quote:

Originally Posted by Unobtanium (Post 984313)
I'm staying stock 357/389. If I wanted more I'd go srt8. My fear was than 2nd prime. I've heard flooring it from a roll is a nono?

I never heard that one, so I honestly cant tell. but from others it don't become an issue until you start throwing some power at it. stock, you should be fine

Unobtanium 03-01-2014 02:44 AM

Re: 545rfe reliability/durability (2010)
 
Yay :)

greenwayer 03-04-2014 10:19 PM

Re: 545rfe reliability/durability (2010)
 
Quote:

Originally Posted by Unobtanium (Post 984325)
Yay :)

Second prime is weak on these trannys, as the clutch packs are too thin for the 2nd prime gear. If you are staying stock dont worry about it, ergo its ok for you to floor it from highway speed, which shifts it into 2nd prime. Flooring from a roll, under 40 mph, shifts it into first gear, not 2nd prime, anyways. DONT TUNE THE TRANNY! No diablo BS tranny shift point tuning it will kill the tranny. Guys with stock cars and a diablo are killing their trannies left and right.

Strongjeff 03-04-2014 11:10 PM

Re: 545rfe reliability/durability (2010)
 
Quote:

Originally Posted by greenwayer (Post 986526)
Second prime is weak on these trannys, as the clutch packs are too thin for the 2nd prime gear. If you are staying stock dont worry about it, ergo its ok for you to floor it from highway speed, which shifts it into 2nd prime. Flooring from a roll, under 40 mph, shifts it into first gear, not 2nd prime, anyways. DONT TUNE THE TRANNY! No diablo BS tranny shift point tuning it will kill the tranny. Guys with stock cars and a diablo are killing their trannies left and right.

Good catch bro, I had forgotten about that

Unobtanium 03-05-2014 04:35 AM

Re: 545rfe reliability/durability (2010)
 
Quote:

Originally Posted by greenwayer (Post 986526)
Second prime is weak on these trannys, as the clutch packs are too thin for the 2nd prime gear. If you are staying stock dont worry about it, ergo its ok for you to floor it from highway speed, which shifts it into 2nd prime. Flooring from a roll, under 40 mph, shifts it into first gear, not 2nd prime, anyways. DONT TUNE THE TRANNY! No diablo BS tranny shift point tuning it will kill the tranny. Guys with stock cars and a diablo are killing their trannies left and right.

So...is that asking for trouble, if I floor it from highway speed stock, as in, is it "on the edge and I'm gonna kill it if I keep it up", or is it "just fine, whatever, should last until the vehicle rots around it"?

greenwayer 03-05-2014 05:08 AM

Quote:

Originally Posted by Unobtanium (Post 986626)
So...is that asking for trouble, if I floor it from highway speed stock, as in, is it "on the edge and I'm gonna kill it if I keep it up", or is it "just fine, whatever, should last until the vehicle rots around it"?

If your jeep is stock it's just fine.

Unobtanium 03-05-2014 05:40 AM

Re: 545rfe reliability/durability (2010)
 
Quote:

Originally Posted by greenwayer (Post 986631)
If your jeep is stock it's just fine.

Is it a power thing, or a wear thing. As in, I am creating zero abnormal wear due to my power levels, and all is well, or what?

I guess what I mean, is it like a 180# guy jumping on something, it will NEVER break, vs a 300# guy jumping on it, or is this 180# guy jumping on it gonna snap it eventually?

Hard to convey what I am going for : /

I'm bone stock and staying that way.

Frango100 03-05-2014 08:05 AM

Re: 545rfe reliability/durability (2010)
 
I have a 5-45RFE in my 2004 jeep. As far as i know there where very little changes over the years, besides some changes in molded piston seals and ofcourse the solenoid pack. Im not sure if they increased the line pressure (the working pressure for the clutch packs) for use with the Hemi.
The transmission itself is reliable as long as you perform the normal services in time. My 5-45RFE needed a rebuild at 150.000 Km due to a worn OD clutch.
During the rebuild (which i did myself after a "specialist" f...ed it all up), i installed a transgo shiftkit. This shiftkit has a resistor which will "fool" the TCM so that it will regulate to a higher line pressure. This higher line pressure will give higher holding forces for the clutch packs, so will minimize any clutch slip (so less wear and less heat buildup).
An other advantage of the shift kit is that it will reduce clutch wear due to shorter shift overlap times. When the transmission shifts gear, it will apply a clutch pack and then releases an other. The time that both clutches, which have different speeds, are pressurized, is called the overlap time. During this time most of the clutch wear occurs, because one of the clutches or both have to slip to make the shift happen. So the shorter the overlap time, the less wear and heat buildup (due to the friction of the clutch discs) occurs.

jeepgcoman 03-05-2014 12:27 PM

Re: 545rfe reliability/durability (2010)
 
I've modded my Hemi so it now has about 100 hp more than stock.....see signature. Right after I bought the WK I added the Sonnax Line Pressure Booster to the 545RFE and it made noticeable difference.....after the TCM figured out what was going on. It raises the line pressure by ~15-30 PSI and does the same thing that Frank's "resistor" does.....increase clutch clamping pressure. I've also been running the Superchips Advanced Transmission Tuning Application with my custom shift schedules/torque management (along with the Sonnax) for over 40000 miles now, all without issue, and believe me I give mine a liberal workout, daily. Anyone that says not to do mods. to the line pressure/shift schedules/torque management is totally wrong, IMO. If it's done correctly, there should be no problems, and the transmission will work much, much better than the crappy stock settings.

I've also tried the Diablosport trans. tuning (I have both tuners), but didn't care for it, mostly because it only allows for upshift schedule changes to 1st, 2nd, and 3rd, and does not allow modification to downshifts or torque managment settings. The SC tuner allows for mods. to all forward gears (up and downshifts), and both light and WOT torque management settings. Every one of my settings are significantly different than stock, and most people probably wouldn't know it was the same transmission.


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