68RFE sprag failure with explanation

[@Rider1Stop]

I just bought yalls 68rfe 900hp transmission can't wait till it comes in and I can get it install, heard nothing but great things about y'all's work.

[@markstolk2499]

great video ! thanks .

[@gregmartin8804]

Great job keep it up can’t wait for more videos

[@jonathanbecerra1765]

Great video and information. Thank you.

[@wpdevelopments]

Thank you for watching! This YT thing is a whole new deal 😂

[@team1up691]

Awesome information here thank you!

[@wpdevelopments]

Be ready for the next! I haven’t made up my mind yet but it’ll be a good one. Thank you!! 🎉

[@aaronolsen8787]

Great video! Thanks for taking the time to make it. I'm really looking forward to watching your future video on the OD clutches in the 68rfe. That is, if you're still planning on making it. Subscribed and waiting!

[@DSGB2199]

Maintenance, maintains preach preach

[@73cjproject]

Great video and tech info! Thanks for taking the time to help it make sense.

[@wpdevelopments]

Thank you for watching! Hope it helps a lot of people now and in the future!🎉

[@Tranibob]

Great job on the first ever video. So happy to see I am not the only one that can't draw anything 😂

[@wpdevelopments]

😂 I never claimed know much or draw ✍️ but we are out here! 😂😂😂 thanks for watching! I’ll have more. I’m going to set up a area just for videos

[@UntamedCustomFab]

Awesome video

[@masonjones6609]

Awesome video can’t wait for the next!

[@wpdevelopments]

Thank you for the support!!

[@seavisions]

What would cause loss of all forward gears and no reverse in a 68rfe?

[@jaythacker5160]

Ethan, so in 5th gens with the separate TCC solenoid does the L/R solenoid keep holding the L/R clutch like we want it to thru the 1-2 shift when we demand it in the tune?? Great vid

[@wpdevelopments]

So technically it could very well work in tuning. If you have a snap on scanner you can watch the L/R pressure switch to verify it’s staying on… since the SSV never needs to stroke in a 5th gen it’s crazy to me they even put it in there.. thanks for watching! If I test prior to hearing back I’ll comment!!

[@jaythacker5160]

@@wpdevelopmentsExcellent, I'll hook up to the ole lady's 24 and watch it. She's getting pissed I play with it more than she does. Thank you

[@BillyWillicker]

To be clear. The low sprag, on an RFE is well protected by the electro-hydraulic strategy in the OE system. In N-D engagement, there is no load applied to the low sprag as the low-reverse clutch is already applied and holding, as with a P-R engagement, and a P-D engagement that is again running through a N-D engagement. The clutch holds until 8mph, releases the LR clutch and then upshifts 1-2 by applying the 2C clutch with no overlap/bind of synchronous shift. There is no shock load to the low roller in an RFE unless you lose traction above 8mph and then regain traction before the 1-2 shift - not likely. In reverse, the LR switch valve shuttles and cuts off oil feed to the LR pressure switch. The pressure switches are only monitored/active in forward ranges. If you tune to see LR pressure switch closure in reverse, it will never see it. Look over the oil diagrams... Very few people really know these units well.

[@BillyWillicker]

Holding the LR clutch on until the 1-2 shift WILL cause a bind. The '19-up units will be less of a bind than '18-back as they have an enhanced reverse circuit. The reason for this is because that will change the shift from an additive or non-synchronous shift into a synchronous shift. The valve body cannot exhaust the LR clutch oil fast enough to release the LR clutch before the 2C clutch applies, it must be fully released before the 2C applies and the OE tuning releases it long before the 1-2 upshift command. The 2C and 4C clutches are the two fastest applying clutches in the RFE, and the LR clutch is one of the slowest releasing as at 8mph it is designed to release slowly to gradually transfer the full load of 1st gear to the low sprag.

[@wpdevelopments]

@@BillyWillicker We have studied this unit probably as much as anyone in the development program. We have every fluid path memorized on top of we are one of the only ones with pressure taps on every circuit in the 68rfe with intense data logging. Your L/R prime function makes it even worse if you think about it because no matter what as you stated if you leave L/R on too long you get a bind in 1-2. So the sprag isn't initially loaded off the hit then the clutch releases and shocks the sprag. We actually made a SSV that hydraulically feeds the L/R clutch all the way through 1st gear and when the SSV strokes from 2C oil it shut it off. We have made this real and I believe we are the only ones ever to make it work or even try it. As well as you might be familiar with the stock tuning but our customers in high HP or HD applications all have aftermarket TCM tuning. There for 8mph isnt enough to hold throughout the 1st gear. If you start the clutch holding first then once you are moving along and drop the clutch it does indeed shock the sprag with whatever load the clutch was holding at the time of release. Do you have internal strain gauge data? but in all thank you for watching and thank you for the input man!! I really enjoy talking to others about this stuff!