Transmission troubleshooting 545RFE+Hemi

[Windex]

Sorry for the long post but providing detail both to see if anyone has had something similar and also so that if someone in the future has similar issues my troubleshooting might help them along the way.

Key details

1. 2005 Hemi with 220,000 kms on it
2. Transmission serviced and pressure sensor replaced @ 206,371 kms
3. Superchips Flashpaq tuned for the past ~10,000kms

Started up after about a week of sitting. Reversed out of carport and then went to head up my drive but drive wouldn’t engage so rolled back. Hit the breaks and left it in park for a bit to see if it would engage after that but no luck, extra revs and it threw itself into limp mode (3'rd gear). Checked the fluid and there was some there and no massive gushing leak so was confident that it wasn’t running on zero fluid. Managed to reverse up driveway and parked and pulled the following codes.

• P0700: Transmission Control System (MIL Request)
• P0107: Manifold Absolute Pressure/Barometric Pressure Sensor Circuit Low
• P0731: Gear 1 Incorrect Ratio
• P0876: UD Pressure Switch Rationality

The MAP sensor one pops up a bit, I've replaced it and it still seems to surface about once a month but I clear it and happy days afterwards.

Cleared the codes and took it for a drive to heat the fluid up so I could get a better read on the fluid levels, seemed to drive fine on a mix of mid to low speed roads for about 10 minutes, no major inclines were involved here. Checked the fluid while it was running and seemed quite low so went and bought some more ATF4+ for it and put about 1L in and she was reading in the area for hot temp. Thinking that was all it was I headed out later that day to hit some tracks, and the same issue started to surface when I was climbing hills, the transmission appeared to slip a bit then catch (almost like it was sucking some air then getting fluid again). Gave up and limped into camp and checked fluid again and pulled the following codes again:

Same

• P0700: Transmission Control System (MIL Request)
• P0107: Manifold Absolute Pressure/Barometric Pressure Sensor Circuit Low
• P0731: Gear 1 Incorrect Ratio
• P0876: UD Pressure Switch Rationality

New

• P1790 Fault immediately after shift
• P0869 Transmission fluid pressure high
• P0932 Hydraulic pressure sensor circuit

Next day was still getting the same slipping behavior in 1st gear but beyond that she was driveable so drove the 2 hours home without major issue, other than some minor slipping when doing low speed stuff through towns (traffic lights and such).

After some reading I think I'll start with looking at the wiring for anything totally obvious but seems unlikely due to just appearing out of the blue but worth a shot, then I'll drop the pan and look at the filters as there are a few reports of the filters splitting and sucking air causing similar issues.

[Windex]

After doing what I could electrically over the past days I decided to drop the pan and found I was the lucky recipient of a split filter! Pics below to paint the full picture.

Seems that at some stage the front bolts have been enlarged or perhaps thats from from factory. Pan magnet didn't have metal in it but the pan did seem to have a bit of clutch material to it and the fluid smelt a bit burnt to me (far from a expert). I am hoping that this is my fix but seems that its been like that for awhile so I'll be crossing my fingers.







Interesting TSB
http://dodgeram.info/tsb/2006/21-007-06.htm

[Gojeep]

Hope a new filter and oil change is all that is needed! Be good if it was.

[ren0vator]

If it's an electrical issue high probability it will be isolated to one gear
Other electrical issues would then revolve around Transmission Control Unit
Then you start to get random shifts etc
But rarely slip and failure to engage any gear

It seems you are describing an intermittent pressure loss
1) Blocked pickup (as you've found dodgy filter)
2) Torque converter issue

Don't worry about the black stuff
That's how every auto trans looks after 100+ kms
Just wipe it out with a rag
There's gunna be a few litres left in the torque converter & lines
Try flushing out the cooler too

[Windex]

Originally Posted by ren0vator

If it's an electrical issue high probability it will be isolated to one gear
Other electrical issues would then revolve around Transmission Control Unit
Then you start to get random shifts etc
But rarely slip and failure to engage any gear

It seems you are describing an intermittent pressure loss
1) Blocked pickup (as you've found dodgy filter)
2) Torque converter issue

Don't worry about the black stuff
That's how every auto trans looks after 100+ kms
Just wipe it out with a rag
There's gunna be a few litres left in the torque converter & lines
Try flushing out the cooler too

Thanks for the reply mate! Glad it happened after the move, the Jeep has done some good miles during the move Vic to Syd with a empty 10x6 then back to Vic with a fully 10x6, towed like a beast too although my fuel consumption was a little savage.

I'm thinking I wont do a full flush just yet as I want to ensure the issue is resolved and everything is shifting happy again as if I have to drop the pan to get to the valve body or similar I'd rather not throw all that fresh fluid away knowing that the older stuff is only ~15,000kms old.

Currently waiting for my filters to arrive, will be interesting to check the old part number on the screw on filter as that was blamed for some early 545RFE's filter splits.

[Windex]

Well both of the filters I removed were non genuine so time will tell if the new ones are any better, went with the newest revision of Mopar ones I could find and they both installed fine, the only external difference was the snout of the new screw on filter was a little shorter (maybe 10 mm) but it's still engaged fine and I screwed it down to the required level.

More importantly after filling it back up (reused the cork pan gasket) the issue appears to be gone!

Still trying to get the right fluid level as I just cant seem to get it up to the right level when hot but we'll get there. I'll keep trying to get the fluid level right and will be watching it closely but it appears to be normal again other than the engagement on first startup (might be a valve body thing).

[Gojeep]

Hope it holds.