68rfe

slownoma

New member
1st-3rd gear it seems I have no issues. 4th on up it seems it slips? If I apply a little throttle it will come out of lockup it seems. If I'm very careful I can get it to cruise around 65-70mph without issues till I see an incline in the road. Also, twice now I've had it hang up in 4th. Stop the truck and cycle the key and I can run back through the gears.

I did take all the connections off the transmission and cleaned them. Also used dielectric grease when reinstalling them.

Any help would be great! From what I've been able to find it seems like it could be 30,000 different things...

Thank you in advance
Jeremy
 
Literally exact same issue my comp68 has.

Likely selonoid pack! Check all electrical including battery supply and alternator. Also when you pull the oring check the C2/C4 input sealing inserts and look for washing out which obviously is line pressure leak.

Anytime the RPM sees a glitch or drop in volts it wants to clear out the learned CVIs, eventually learning itself down to 0..... mine was at 8 last time I looked.

Also see if you can pull TCM codes with an H&S product, or high end scan tool.

My codes when stuck in 4th were
P0714(trans temp sensor signal)
P0713(trans temp sensor intermittent)
P0871 (pressure switch rationality)

All 3 being linked to the selonoid which the temp sensor is in and the moment that code is thrown it attempts to restart a learn.

These packs are known for being complete $HIT. According to Suncoast, theyve had quite a few brand new oem units delivered from supplier DOA. Even the guy that goes on all the Cummins based forums for 6.7s (Transengineer) who was apart of the design team and still with FCA says the selonoid are such crap they're TSB step one in most 68rfe issues.
 
Literally exact same issue my comp68 has.

Likely selonoid pack! Check all electrical including battery supply and alternator. Also when you pull the oring check the C2/C4 input sealing inserts and look for washing out which obviously is line pressure leak.

Anytime the RPM sees a glitch or drop in volts it wants to clear out the learned CVIs, eventually learning itself down to 0..... mine was at 8 last time I looked.

Also see if you can pull TCM codes with an H&S product, or high end scan tool.

My codes when stuck in 4th were
P0714(trans temp sensor signal)
P0713(trans temp sensor intermittent)
P0871 (pressure switch rationality)

All 3 being linked to the selonoid which the temp sensor is in and the moment that code is thrown it attempts to restart a learn.

These packs are known for being complete $HIT. According to Suncoast, theyve had quite a few brand new oem units delivered from supplier DOA. Even the guy that goes on all the Cummins based forums for 6.7s (Transengineer) who was apart of the design team and still with FCA says the selonoid are such crap they're TSB step one in most 68rfe issues.


Kevin, text me back brother..
 
This is what i'd buy if I were going in there: Service Kit
72420SK1CTP1.jpg
 
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Thanks for the replies folks! Joe and mike at joker fab are nice enough to toss a scanner on it tomorrow to see what codes were showing. I'd hate to spend 250$ if that's not the issue. If I were 95% sure that was the fix id buy it today. Otherwise that money will be going towards the purchase of a new trans/converter.
 
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