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68rfe year model difference

24K views 15 replies 7 participants last post by  32lupe32 
#1 ·
What, if any, differences is there in each year model of 68rfe? Are there any design/improvements over the year models?
 
#5 ·
The 11.5 and 12 have slightly better torque converter but all models still have the same weak point which is the 5-6th gear clutch packs, they don't like being hot rodded or run extremely hard and burn up.
 
#7 ·
Solenoid pack in V/B was also Changed out, but I think you can run the newer ones if you change to the earlier Solenoid packs.
 
#8 ·
Input shaft has been the same size all along. Yes, the converter was improved for 2012 MY. Started using a common oil pan (same for 4x2 and 4x4, with "4x4-style" filter) in 2010 MY.

Biggest change (from an interchangeability standpoint) was removal of the OD solenoid for 2011 MY. A new-style (2011+) solenoid module will NOT work in a 2007-2010 truck. An older-style solenoid module WILL work in a 2011+ truck. There were also changes to the valve body separator plate for 2011 MY (to support the solenoid change), so if you want to use a 2011+ valve body assy in a 2007-2010 truck, you should swap out not only the solenoid module but also the separator plate (keep the old separator plate in the 2007-2010 truck).

Also introduced an anodized valve body housing for 2010 MY (for improved durability). The 2010+ valve body housing (but not necessarily the solenoid and separator plate, as noted above) will work in 2007-2009 trucks (and is preferred). The Mopar service valve body assy for 68RFE is a 2010-style assembly (with anodized housing, but still with old-style solenoid and separator plate) so it will work for all model years.
 
#11 ·
The only other significant change has been the torque converter K-factor (performance curve), which has been changed a couple times. The converters are all interchangeable, as far as actually fitting / bolting in, but the performance (stall speed, etc.) has changed somewhat. This could potentially give you some issues if you use the wrong K-factor (like no upshift during WOT accelerations), but I don't know the details (whether the shift schedules were modified for the various K-factors, how the K-factors compare at higher speed ratios, etc.), so I don't know whether using the "wrong" K-factor will actually give you any problems. I suspect that it would NOT cause any problem, but I have to give you the caveat just in case.
 
#12 ·
How will that change affect older models if a newer trans used with the updated electronics is installed. i.e. an older pcm flash vs correct year model?
 
#13 ·
Are you asking about the converter change? And what would happen if you installed a newer converter into an older truck? If so, the answer is: I do not think there would be any significant adverse effect, but I cannot say that absolutely since I do not have the detailed information I would need to confirm it.
 
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