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-   -   think my tranny is going... (http://www.jeepgarage.org/f181/think-my-tranny-is-going-43812.html)

tig488 06-24-2012 10:43 PM

think my tranny is going...
 
ive read a few threads on this before and nothing about what causes it or how to fix it.

i have an 05 hemi, with 115K miles. ive had this slight studder for years but it seems to be getting worse. it happens when accelerating in the low rpm range when it should downshift but doesnt. it feels exactly like when youre driving a manual and try to go up a hill in too high of a gear and the car bucks. if i shift it myself it rarely does it because i can control the shift points. i added some fluid but no help.

tranny replacement?

Escape 06-25-2012 12:42 AM

Re: think my tranny is going...
 
Trans sounds mechanically fine.

Any codes?
Have you ever had it serviced (trans and engine)?
Correct spark plugs and are they properly gapped?
What does the fluid look like when you pull the dipstick out and place a dot of fluid on a piece of white paper?
Have the filters ever been changed?
Water in the fluid (looks like chocolate milk)?
Dropped the pan and looked for shavings/chunks?

If it's in the trans I'd say it's in the solenoids/fluid/sensors/filters or valve body.

If it's not slipping get it serviced.

tig488 06-25-2012 09:28 AM

Re: think my tranny is going...
 
i changed the tranny fluid and tranny filter at 65K miles. i use Castrol ATF4+ fluid. the engine is spot on, no issues with that. i dont get any codes,even during the surging it never throws a code. the fluid on the dipstick is still pink/red.

1st, 2nd, and 3rd gear changes are fine, if the rpms are over 2k. once it goes into 4th and OD, if the rpms are below 2K it hesitates with acceleration. i can even hold it steady and it will buck and stutter as long as i hold it there. then, if i stomp on it, it downshifts and goes, OR, goes into a kinda limp mode where it wont go just revs, then i have to let off for it to engage, then its fine.

ive changed the EGR, plugs, fluids, air filter, cleaned the TB, and have no CELs, i thought it might be low tranny fluid so i added some but it didnt help.

i called the jeep dealership, they said more than likely the filter and fluid are fine since i did it at 65K. i saw a TSB about something similar to this. i wonder if the shift points are out of spec. it feels exactly like trying to go uphill in a stickshift in too high of a gear.

brentwoodkris 06-25-2012 10:03 AM

Re: think my tranny is going...
 
Maybe your MDS is screwing up?

jeepgcoman 06-25-2012 10:53 AM

Re: think my tranny is going...
 
Probably the easiest (and cheapest) way to beat this is to do two things.....get a Sonnax Line Pressure Booster, and a Superchips Tuner with the Advanced Transmission Tuning Application. Then you'll boost the trans. clutch clamping pressure and you can set the up/down shift schedules to suit your needs/desires. I've got both on my Hemi, and everything works great.

I'd also do another trans. service since it's been quite a while since you last did it.

tig488 06-25-2012 02:08 PM

Re: think my tranny is going...
 
all good ideas, thanks guys, keep em coming.

ill probably do a tranny service to see if that helps.

Escape 06-25-2012 10:26 PM

Re: think my tranny is going...
 
Quote:

Originally Posted by tig488 (Post 647746)
1st, 2nd, and 3rd gear changes are fine, if the rpms are over 2k. once it goes into 4th and OD, if the rpms are below 2K it hesitates with acceleration. i can even hold it steady and it will buck and stutter as long as i hold it there. then, if i stomp on it, it downshifts and goes, OR, goes into a kinda limp mode where it wont go just revs, then i have to let off for it to engage, then its fine.

The reving without going is concerning. Do you have the limp mode dash lights when this happens? If not that sounds like a worn clutch pack.

I would do as suggested above and get a tuner for it and retune that trans as the factory settings suck and go from there. :thumbsup:

2005JGC 06-26-2012 02:30 AM

Just so its said... The aforementioned additions WILL NOT FIX ANYTHING. They may mask the problem (unlikely) but they will not fix your complaints.

*edit* Im not trying to be a douche with my response, I just want to make sure its known that adding modifications to the outside of a transmission will not fix something failing inside it might cover up the effects of the failing item(s) but will not fix anything.

Has it gotten worse or is it something that has just kinda been there for a long time? As suggested with the MDS, I have felt some less than stellar drivability from the MDS, just feeling like its taking too long to kick out. Ultimately this may be something you need to get to a shop... I will say even if you are a diy'er pulling this trans on your back in a garage would be HELL... impossible no, but HELL, yes.
Sent from my SCH-I500 using Tapatalk 2

tig488 06-27-2012 12:51 PM

Re: think my tranny is going...
 
not a single CEL or dash light comes on during this.

jeepgcoman 06-27-2012 07:00 PM

Re: think my tranny is going...
 
2005JGC, I am sure no one is thinking you're a douche. Speak your mind man, LOL! IMO, the 545RFE is a little (actually quite a bit) lacking to begin with, and if there are no real problems after servicing and verifying it's working as the DCX folks say it should, then adding the "masks" is a pretty good way to resolve some of the built in problems many of us complain about. It's hard for me to say, but with the line pressure booster and the ATT App., I am now actually fairly satisfied with the way it operates. In tig488's situation, I'd for sure start with a trans. service, especially if he's unaware of the past maintenance history, or hasn't serviced it in a while.

As far as the MDS goes, you're right. Even the way mine is set up, the MDS is sometimes a little goofy. Most of it happens when it's right on the cusp of meeting the torque %age requirement for activation. In that case mine will hunt, and I just backshift a gear if it gets too bad. Mine, with the SC tuner, also is a little harsh on the disengagement, but engagement is normally good.

tig488 06-28-2012 09:06 AM

Re: think my tranny is going...
 
so today i drove it in tow/haul mode, and it ran almost completely normal. granted the shift points are different in that mode so the rpms change and theres no OD, but it didnt hesitate at all. mpg is a little lower but runs much much better. it also ran a little better with TCS off. not saying those are fixing it, i was just trying anything.

paroxysym 06-28-2012 09:26 AM

Re: think my tranny is going...
 
mine does the same thing... feels like its lugging it in the higher gears- like it should downshift but it doesnt, until you punch it then it knocks itself down a gear and goes. i change my fluid every 15k as advised by a mechanic friend that works for jeep. these trannies can take a beating and surprisingly have had no problems.

maybe you should reset your the adaptives- disconnect the battery and let it set a few minutes, turn the headlights on and hold the brake for a minute. supposedly it clears your comp.. then when you connect and take it for a drive it relearns everything. i do this when i update my tune and such.

as for the comment about the sonnax line pressure booster- i plan on grabbing one of these. i dont see it as a mask, i see it as firming up the shift points on a tranny that already has some sloppy shift points from the factory. lets face it, if it didnt have autostick half the time- you would be fed up with it..


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