545rfe vs 645rfe Torque Converter Compatibility?

[Jared Worley]

Ok. So I have been trying to research the difference between the 545rfe and 65rfe converters. I'm considering upgrading mine while I have engine/trans pulled if I can find a cheaper rebuilt one. I have a 65rfe trans that I am swapping in. Based on my research I am confused. Several vendors sell a 545rfe converter that they say is compatible with the 65rfe. Others have stated that these are not compatible. What gives?

What I know is that the early 65rfe's appear to have the same 4 bolt circle and spacing but that the overall size of the stock units was slightly larger in the 65's. I would like to have a 2600-2800 stall but don't want to spend 600.00 on one of the performance units at this juncture. I'm seeing rebuilt ones under 300 which suits my budget.

Is running a smaller circumference converter going to hurt anything. This is a mild street truck with a few mods and will have little/light to no towing. Currently has the 3.92 gears which are staying for now - 2WD

 

[Jared Worley]

This is also for a 2013 65rfe in a 2009 1500 5.7 that originally had the 545. Same trans, different programming and otherwise structurally compatible. I'm still fuzzy on the differences in converters other than size. It looks like the 65rfe uses the same 10" 4 bolt circle mount but 10mm x 1.5 bolts. The earlier 545 converters use 5/16 x 24 bolts. It seems like it would be easy to either tap the converter for the 10mm modern mounting bolts, use 10mm OD ferrules in the Flexplate, or use a tap and die set on the 10mm bolts to turn down to 5/16 x 24.

The aftermarket performance parts just drill both patterns in the billet blanks while utilizing the smaller 11.625 converter size.

Any reasons why this wouldn't work?

 

[AndreB]

What happened ? I need to know if I can put a 65rfe into an 09 that originally had a 545rfe for a swap ? I don’t care about the sixth gear just want it to work !?

 

[AndreB]

This is also for a 2013 65rfe in a 2009 1500 5.7 that originally had the 545. Same trans, different programming and otherwise structurally compatible. I'm still fuzzy on the differences in converters other than size. It looks like the 65rfe uses the same 10" 4 bolt circle mount but 10mm x 1.5 bolts. The earlier 545 converters use 5/16 x 24 bolts. It seems like it would be easy to either tap the converter for the 10mm modern mounting bolts, use 10mm OD ferrules in the Flexplate, or use a tap and die set on the 10mm bolts to turn down to 5/16 x 24.

The aftermarket performance parts just drill both patterns in the billet blanks while utilizing the smaller 11.625 converter size.

Any reasons why this wouldn't work?

 

[AndreB]

Let me know

 

[bigdevk]

I DID IT GUYS! 2014 65RFE INTO A 2009 RAM 1500 THAT HAD THE 545. It's the same trans, but I stuck with the old torque converter and it went in without a hitch. I ended up swapping out the recently replaced shift solenoid in the old trans because the new used trans had a bad solenoid after install. But now with the new solenoid she shifts like a frigging champ!

 

[bigdevk]

Lkq said it wouldn't fit, and that's only true if you are trying to use the newer beefy TC, however there are conversion kits, but IMO the TC wasn't the weak spot of the old trans.

 

[Jared Worley]

About 20k miles on my swap. It's is basically the same trans but I swapped valve bodies and solenoid to earlier version from 09/10. There is an extra check ball in the valve body of the 13 and was told this would be incompatible. I didn't try it to see.