If you're towing with a Jeep or Dodge/Ram with the Chrysler 545RFE and it won't go into gear....try this first......

[Lou C]

OK posted this here because I thought it might be helpful to members who have Chrysler products with this transmission (actually a good unit) who have this problem. Just happened to me last week. 120,000 miles, always shifted great, never had a problem with it all these years, no slips, jerks, noises or leaks. Then I put it into reverse to do some errands and nothing. Fluid level is fine. Popped a P0944 code, loss of pump prime. Did some reading on Mopar/Jeep sites, the possible causes are:
clogged trans filters
loose spin on filter in the pan
split main filter
bad pump
there was also a TSB covering up to the 2006 models that a bad spin on could cause this problem.
So I figured it was worth a shot to try changing the filters....I found the pan was clean not much on the magnet, filters looked good but when I went to remove the spin on, it wasn't tight, could have been the cause, but not sure....So....cleaned up pan, scraped off all the nasty RTV, wire wheeled it clean, replaced filters (you have to be careful with the seal for the main (flat) filter because it should be tapped into the trans case (use a 19mm socket on the extension flat side up) not put on the main filter tube and shoved into the opening in the trans case. Spin on gets like 10 ft lbs. I used Mopar filters. Re-applied the Chrysler auto trans RTV, and re-installed the pan (15 8 mm bolts, they get like 8 ft lbs so just snug), the ones at the front of the pan and passenger side front of the pan are tough to get at because of the cat converter and exhaust pipe, I used an 8mm socket with a built in u-joint to get those in/out).
Other tips, due to the fact that there is no drain plug on the pan and the pan holds 8-9 qts of fluid (this will make a colossal mess if you just crack the pan loose) use a vacuum pump like on your inboard boat engine to suck out as much trans fluid as you can (got out 4 qts or about half), then after you crack the pan loose you can put the hose in the gap and suck out most of the rest, for a nearly no-mess trans fluid change.
Clean the flange of the trans case really well, blow out the bolt holes, clean all the old rtv off the bolts and make sure they will all thread in, you don't want to cross thread or break any of these. After the initial tightening, let the RTV set for about an hr, then go back under and snug em up again. I let the RTV set up overnight before refilling. Filled it up with 8 qts of ATF+4 shifted it though all the gears, let it run for a bit in neutral, and it is just fine, like it always was. Added about 1 more qt after fully warming it up for it to be really full.
So before going into a panic, see if you get the P0944 code, if so, change filters. I had to do this outside when it was 35 degrees out so I had to heat the trans pan with a heat gun just to get the fluid to pump out. If there is a next time I'm using a trans pan with a drain plug and a Lube Locker gasket, personally I'm not a fan of RTV, yes it seals well if you use the right type but it is a real pain to clean it off the pan.

 

[bruceb58]

How often do you change your transmission fluid? I change mine in my vehicles every 30K. Every other change, I change the filter.

Whoever did the last change used sealant vs a gasket?

Super important to use a torque wrench on Transmission pan so you don't warp it.

 

[Lou C]

ChryCo listed 100k under normal service and 60k under severe. RTV is all that the factory used on these; if you want a gasket it has to be aftermarket. I got the little 8mm bolts snug; waited an hr & then re-snugged them. The official spec is 105 in lbs or about 8 ft lbs. No leaks….

 

[bruceb58]

ChryCo listed 100k under normal service and 60k under severe. RTV is all that the factory used on these; if you want a gasket it has to be aftermarket. I got the little 8mm bolts snug; waited an hr & then re-snugged them. The official spec is 105 in lbs or about 8 ft lbs. No leaks….

Yeah...my F-150 lists over 100K. I still change it at 30K.

 

[Lou C]

What I'm going to do is pull a clean sample with my vacuum pump in a couple of years and send it to Blackstone Labs, I've used them for oil analyses on all 4 of our vehicles (3 Jeeps & a Subaru) and the boat. They also do auto transmissions manual transmissions and differentials. That way you know if you are changing it often enough for sure.
The other thing you can do is hook up a good scan tool when towing to read your trans temp, to see how high it gets when towing your boat or RV. Another good guide to how often you should change. I only tow maybe 4 times per year, short distances to launch and retrieve my boat (5050 lbs) and my brother's (about the same).
Since I'm semi-retired and only put 3000-4000 on this vehicle per year (also still drive the old '98 Jeep, with 181,000 miles on it) it will take years to get to 30K miles!

 

[bruceb58]

What I'm going to do is pull a clean sample with my vacuum pump in a couple of years and send it to Blackstone Labs, I've used them for oil analyses on all 4 of our vehicles (3 Jeeps & a Subaru) and the boat. They also do auto transmissions manual transmissions and differentials. That way you know if you are changing it often enough for sure.
The other thing you can do is hook up a good scan tool when towing to read your trans temp, to see how high it gets when towing your boat or RV. Another good guide to how often you should change. I only tow maybe 4 times per year, short distances to launch and retrieve my boat (5050 lbs) and my brother's (about the same).
Since I'm semi-retired and only put 3000-4000 on this vehicle per year (also still drive the old '98 Jeep, with 181,000 miles on it) it will take years to get to 30K miles!

Thankfully, my F-150 shows the trans temp in the cluster(upper right hand in the picture). Max temp I ever see towing a 6000# travel trailer and a 6500# boat is 225°F. This transmission is designed to run at 205°F even when not towing.



I added a gauge to my 1999 Silverado in the dash. The 3/4Ts came with the gauge so there was already a spot for it. I sent my cluster to a shop and they put it in. On that truck I added a trans cooler to it and the transmission temps never went over 190°F

Just added electric over hydraulic disc brakes to my travel trailer. I absolutely HATE drum brakes. Does not matter what type they are....electric or hydraulic.

 

[Lou C]

It would be nice to have the temp readout in the instrument panel. I just bought an Autel Maxi Com scanner this unit will read trans temps in addition to a lot of other functions so when I time the boat next year I’ll see what the temp is. I do understand the disdain for drum brakes but I haven’t had bad luck with them. If I was a trailer boater towing every time I used the boat then I agree I’d spend the $ for full stainless discs. The non stainless discs don’t hold up well here. That’s obvious to me looking at many trailers at boat yards here on Long Island…

 

[bruceb58]

It would be nice to have the temp readout in the instrument panel. I just bought an Autel Maxi Com scanner this unit will read trans temps in addition to a lot of other functions so when I time the boat next year I’ll see what the temp is. I do understand the disdain for drum brakes but I haven’t had bad luck with them. If I was a trailer boater towing every time I used the boat then I agree I’d spend the $ for full stainless discs. The non stainless discs don’t hold up well here. That’s obvious to me looking at many trailers at boat yards here on Long Island…

Problem with stainless discs is very poor heat dissipation so they don't work as well as regular steel discs. They are also a little softer so they wear out faster. I have stainless steel disc brakes on my bicycles and they work well enough though but they have tons of ventilation which you don't have as much on trailer brakes.


I was on the freeway two months ago with my travel trailer. Even with all drums adjusted correctly, I had a heck of a time stopping in an emergency stop. With my 6500# boat trailer with disc brakes, never an issue. I had already planned to upgrade the travel trailer brakes...that one stop confirmed my decision.

 

[Lou C]

You know there was an interesting you tube vid on a problem that you can have with electric drum brakes. I’ll see if I can find it; it had to do with faulty electrical connections that look ok from the outside but are not allowing full voltage to reach the magnet.

 

[Lou C]

take a look at this...
I never had a lack of braking with hydraulic drum brakes, but this could be a cause of mysterious loss of braking with electric systems...

 

[bruceb58]

Yep...there are a lot of reasons not to have electric drum brakes! That's just one of them.

My parents had a triple axle 5th wheel for awhile. They went through a bunch of faulty magnets.

Easiest way to check is to pull the emergency switch release and measure the current. If the current has changed, time to see which magnet is failing.

Also, best thing to do with electric drum brakes is to redo the wiring so it isn't daisy chained like most are wired. Everything shoudl be homerunned to a single point near the front of the trailer.

 

[bruceb58]

The worst thing you can use for ANY electrical connection are those stupid Scotchloc connectors. My trailer used a crimp type that was likely much better. In any case, a homerunned scenario would have crimped ring connectors at a junction box at the front of the trailer

 

[Lou C]

One reason why I prefer hydraulic surge brakes to electric including electric over hydraulic:
the easy of troubleshooting and finding problems before setting out....
On some actuators you can pump the master cyl with a long screwdriver, then you can feel if it is solid, or soft, that will tell you there is a leak, or the master is just worn out, similarly you can just go and look at your brake lines to see if there are any leaks.
I have a habit of always putting some pressure on the master to make sure it holds pressure, checking the fluid level and checking for leaks. I will also jack up each wheel to make sure the cylinders haven't seized up over the winter storage season.
With electrics, I feel that there are numerous potential failure points, that are not as obvious or easy to spot.
Yes I know that electric and electric/hydraulic gives superior control over braking vs simple surge brakes but for me they work just fine. We have some very steep hills, but they are not long, and speeds are like 30-40 mph. Highway towing here is mostly flat, for example the Long Island Expressway is totally flat from Queens all the way to where it ends in Riverhead Long Island. I have heard about very long and steep hills out west where the better control of electric/hydraulic is well worth it, but it comes with extra complications and cost, as always is the case it seems.

 

[bruceb58]

One reason why I prefer hydraulic surge brakes to electric including electric over hydraulic:
the easy of troubleshooting and finding problems before setting out....
On some actuators you can pump the master cyl with a long screwdriver, then you can feel if it is solid, or soft, that will tell you there is a leak, or the master is just worn out, similarly you can just go and look at your brake lines to see if there are any leaks.
I have a habit of always putting some pressure on the master to make sure it holds pressure, checking the fluid level and checking for leaks. I will also jack up each wheel to make sure the cylinders haven't seized up over the winter storage season.
With electrics, I feel that there are numerous potential failure points, that are not as obvious or easy to spot.
Yes I know that electric and electric/hydraulic gives superior control over braking vs simple surge brakes but for me they work just fine. We have some very steep hills, but they are not long, and speeds are like 30-40 mph. Highway towing here is mostly flat, for example the Long Island Expressway is totally flat from Queens all the way to where it ends in Riverhead Long Island. I have heard about very long and steep hills out west where the better control of electric/hydraulic is well worth it, but it comes with extra complications and cost, as always is the case it seems.

I have used them all. Surge drum is the worst. Electric drum is a close second.

Disc surge and EOH disc beat the drum brakes hands down.

EOH disc costs more but it's worth it. I just finished off my travel trailer EOH disc. Total cost was $2400. Expensive but worth it for a trailer I put 10K miles a year on.

If I remember correctly, you only trailer your boat 25 miles each way once a year right? For something like that, just go with whatever is cheap. You don't need anything that good.

Out of curiosity, have you ever used anything but drum surge?

 

[Lou C]

It’s even less than that! 3/4 mile to the ramp 3/4 mile to the boatyard for bottom paint. Longest tow was about 15 miles to the best fiberglass shop on LI to get it painted in red Imron. Drum brakes is all I’ve used. On those very short toes the hills are real steep, no problems stopping it at all.
PS my brothers boat is about the same size & weight as mine and is on a year old Venture alu trailer with surge 12” discs, the 12” drums on mine stop as well, his I tow a bit further when we launch it.