Engine/Transmission (1998.5 - 2002) 47re Spring(s) questions

[DJChaffin]

I've been a member since 2002, and have always found my answers in the forums.

This is the first time I've had to post a question. So here it is, ...



I'm almost done rebuilding the 47re in my 99 CTD 2500, but I have a couple questions before I bolt on the valve body.



When I disassembled my 3-4 accumulator it had two springs, wound together. They springs were apparently so strong that it wore a groove into the cover plate. ?? This was probably done by the last rebuilder 182,000 miles ago. Why? What would the benefit be?

Similarly, the accumulator (intermediate servo) has a spring on both sides of the piston. I've replaced the plastic piece with a Sonnax billet piston. I'm trying to install it, and have to use a big "C" clamp to compress both springs to get the valve body to seat. Is that right? I don't remember that much force behind it when I tore it down for rebuild.



Thanks for your time and consideration.

Dan



p. s. couldn't edit my sig. block today so here's some other maybe relevant info;

• 99 2500 CTD 47re 212,000 miles
  
• EGT, Trans Temp, Fuel Pressure, Boost (Auto Meter/WesTech)
  
• Edge EZ, FAST Fuel pump & new VP44
  
• 4" Exh turbo back w/ straight thru muffler
  

 

[cerberusiam]

The heavier springs on the 3-4 accumulator are to soften the lockup hit. When you raise the pressures and the TC locks it will bang and bark the turbo without some adjustments to how that applies. The accumulators arre supposed to take the big hit out so higher pressures will need more spring to soften the blow. If you haven't, replace the accumulator retainer with an updated piece. They break.

On the accumulator, I think all you need is the spring between the VB and the accumulator. The 2 spring setups were really for the gas engine application. In the 48RE's that spring is gone so you can likely leave it out for a diesel trans. Have to try and see if there is a negative to it. A lighter spring in that accumulator will enhance the shift firmness.

 

[DJChaffin]

Thanks for the info. I'll look for the updated retainer.