abittenbinder
Doktor A (864-623-9110)
I recently posted an offer for my DARF (Doktor A Rsn Fix) kit and response has been disappointingly mild. I suspect that most of the owners interested in RSN mediation have already enrolled in my DARF trials!
The 'kit' was intended to provide tooling (as well as instructions) to make the simple to perform DARF, even easier to perform. I will leave it to owners to source their own tools. It's not difficult.
In the spirit of open source, free software- here's the fix:
The DARF modifies the TCC control pressure and provides mild damping of TCC pressure fluctuations as well.
The fix consists of a calibrated orifice which is drilled into the removable, steel end plate of the valve body, dead center in the TCC spool valve location.
Experimentation here at the Global Sprinter Research Center has shown that an orifice diameter of 0.052" (1.32mm) is large enough to control RSN and prevent over-intervention from TCC pressure adaptation in the TCM while maintaining fuel economy..
Some vehicles will allow control of RSN with an orifice size as small as 0.0465"(1.18mm), others may require a larger 0.055" orifice. But the 0.052" orifice seems to work for most, without penalty of excess fuel consumption.
To keep everyone on their toes, I'll leave it to you, kind owners, to read the service literature and determine which valve body plate is the one in question and which spool valve is the TCC pressure control valve.
Being a softy, I'll give you one clue-look on the drivers side of the transmission.
Please provide performance feedback after you perform your DARF and kindly give me credit when performing this for others.
I am, of course, happy to perform the DARF for any visiting Sprinter owners here at the Global Sprinter Research Center while servicing their beloved Sprinters.
The DARF can be performed with or without a transmission fluid change and service.
Doktor A
The 'kit' was intended to provide tooling (as well as instructions) to make the simple to perform DARF, even easier to perform. I will leave it to owners to source their own tools. It's not difficult.
In the spirit of open source, free software- here's the fix:
The DARF modifies the TCC control pressure and provides mild damping of TCC pressure fluctuations as well.
The fix consists of a calibrated orifice which is drilled into the removable, steel end plate of the valve body, dead center in the TCC spool valve location.
Experimentation here at the Global Sprinter Research Center has shown that an orifice diameter of 0.052" (1.32mm) is large enough to control RSN and prevent over-intervention from TCC pressure adaptation in the TCM while maintaining fuel economy..
Some vehicles will allow control of RSN with an orifice size as small as 0.0465"(1.18mm), others may require a larger 0.055" orifice. But the 0.052" orifice seems to work for most, without penalty of excess fuel consumption.
To keep everyone on their toes, I'll leave it to you, kind owners, to read the service literature and determine which valve body plate is the one in question and which spool valve is the TCC pressure control valve.
Being a softy, I'll give you one clue-look on the drivers side of the transmission.
Please provide performance feedback after you perform your DARF and kindly give me credit when performing this for others.
I am, of course, happy to perform the DARF for any visiting Sprinter owners here at the Global Sprinter Research Center while servicing their beloved Sprinters.
The DARF can be performed with or without a transmission fluid change and service.
Doktor A
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