Service Interval on 45RFE / 545RFE

[Gene K]

Ive seen a couple of the 45RFE / 545RFE Transmissions go around 250,000 miles on the original ATF+4 and Filters (It has two filters). In both cases the diagnosis was pump failure.

I wonder if the transmissions would still be alive if the filters had been changed even with the original fluids.

Anyone want to suggest a fluid and filter change interval? Im only planning on doing partial changes (13 Pint Service Fill) not a flush.

Owner's Manual suggest 60,000 Miles for Severe Duty. Im thinking every 3 years (30,000-36,000 Miles) for Service Fill.

 

[The motor guy]

I have the 68rfe which I believe is based off the 545RFE. It calls for 60,000 mile service under severe service applications and 120,000 under normal duty service. I was thinking of doing mine like every 30,000 and then maybe replacing the filters every other time. Usually every 30-40,000 miles is pretty much the average time for fluid changes on an automatic tranny. When I do the first change i am going to install a drain plug to make changing easier in the future. Then i'll change during two drain and refills for each service. I personally don't believe in these 100,000 mile fills that they recommend in some of these vehicles. Remember heat is the enemy of every auto tranny. I suppose if you stay under 200 degrees then it could go 100,000 miles but that usually doesn't happen. But hey what you are doing sounds great. Remember most people don't do anything at all. I would also recommend just dropping the pan. Don't use any flush machines.

 

[Gene K]

Im sure it helps that the ATF+4 is a high VI G3 Basestock. I suspect both trans I saw died from pump starvation when the filter plugged. Still impressed they lived 250,000 miles with no service in a 5500 lb V8 truck.

 

[440Magnum]

I plan to go with fluid/filters somewhere between 60k and 80k in our 08 Ram 1500. It doesn't see lots of towing, but a fair bit of heavy hauling.

The 545RFE is turning out to be as brutally rugged as the old Chrysler 727 and 904 transmissions were. And its about time, after all the problems back in the 90s with the front-drive Chrysler-designed transmissions. The 90s rear-drive truck transmissions were a mixed bag- they were basically just a 727 with an overdrive in the tailshaft. I have used A-518 rebuild kits in a 727, they're that identical. The 727 part would last forever, but the O/D section was the weak spot. But I have had one of those go well over 200k (on the original fluid, despite my protestations to change it) in a 5.2L 1992 Dakota. In fact that truck is still going.

There's no question that the troublesome minivan front-drives (41TE and cousins) had some physically weak components, but I do have to wonder how much better they would have held up if ATF+4 had been available instead of ATF+3. A few years back I read an SAE paper comparing ATF+3 and ATF+4, and there's no comparison. ATF+3 was just horrible on several scores, oxidation rate being one of them. ATF+4 outscored Mercon V and Dexron VI on most measures, although it wasn't a big margin. The combination of a solid design like the 545RFE and a superior fluid like ATF+4 is definitely helping these trucks live longer.

 

[Gene K]

Originally Posted By: 440Magnum
A few years back I read an SAE paper comparing ATF+3 and ATF+4, and there's no comparison. ATF+3 was just horrible on several scores, oxidation rate being one of them. ATF+4 outscored Mercon V and Dexron VI on most measures, although it wasn't a big margin.


Actually ATF+3 is pretty good when compared to ATF+2.

 

[440Magnum]

Originally Posted By: Gene K
Originally Posted By: 440Magnum
A few years back I read an SAE paper comparing ATF+3 and ATF+4, and there's no comparison. ATF+3 was just horrible on several scores, oxidation rate being one of them. ATF+4 outscored Mercon V and Dexron VI on most measures, although it wasn't a big margin.


Actually ATF+3 is pretty good when compared to ATF+2.


Which is kinda like saying Dexron I is pretty good compared to Type A....

 

[rslifkin]

I'd personally plan on changing the fluid in the pan, as well as the filters around 50k. Of course, keep an eye on fluid condition. If it's been used hard, and at 30k the fluid starts to look or smell a bit off, change it early.

 

[SEMI_287]

I changed the fluid in my 545rfe at 160k. Previous owner maintenance fail. It runs perfect, nothing odd at all. But I would change it every 30k to be safe.