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AW71 free accumulator mod


Owner: DeathWagon
300+ Club
Jul 3, 2005
Montgomery Alabama
Even better than the valve body mod is the new and heebspeed improved... There are these pistons in the transmission called accumulators and they act kinda like shift shock absorbers.. There function is to make a nice smooth shift and to make old ladies happy with there volvo.. The bad thing about them is that they cause a short slip during the shift to make it smooth but during that slip on high hp volvos the clutches in the trans get super hot and wear out.. By adding a spacer inside of the accumulators spring you reduce the shift time by reducing the time it takes to fill the piston up with fluid.. I took each spring and cut some heavy rod about 1/8 inch shorter than the spring is fully extended.. Do this to each one of the accumulators springs in the trans and you will get much faster shifts and should still have a driveable trans... This was super easy and should actually make the trans last longer..
Sorry there are no pics my camera was dead..

UPDATE 4 years after original post..

Kenny and myself picked up a project to help out a local Tbricker Jim and replace his 850 auto trans.. We dident feel that it would be right to go threw all that work of swaping out the transmission without making some sort of upgrade so here are our pics and video from the same mod done to an 850 turbo transmission..

enjoy the pics and video..

removing the valve body

remove only the 10mm bolts and the valve body should lift right off.. dont forget to carefully remove the shifter arm as your picking the valve body up.. this can be difficult when reinstalling..

whats under the valve body..

on the 850 trans the accumulators are located on the valve body its self.. remove the 6 black 10mm bolts but be prepared its spring loaded..

here is what my shim looks like beside the spring.. the shim is about 1/4 shorter than the spring fully extended.. the shim fits nicely inside of the spring.. We used a cut off 14mm bolt for a shim..

and the shim inside of the spring..

here are a few short clips to give you and idea of how the accumulators should squish after the shims have been added..

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Enjoy guys.. and from the looks of things this could be done with the transmission in the car but its defiantly easier with it out..

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Sounds like sam has been hangin out with Hydramatic guys..

Be really careful about where you shoot air in those things.. Wear safety goggles.
Sam you'll have to give me a ride in it so I can do a butt comparison to my AW70 that I have now, the slipping one I had with the last car, and the AW71 i repalced it with :) I do hate how it's soo soft and dull.