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8 speed fluid and filter change

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you could add a by-pass trans filter to it, and not have to deal with draining the pan anymore..
I wish there was a kit for it... I'd go for it.

Next time, I'm siphoning the old fluid out, add fresh fluid and call it a day. The filter will be ok without replacing.
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amsoil might sell a by pass kit


i'm gonna try running this full flow on my truck next. no bypass, just straight thru. i tried a spin on Derale adapter, work well but i feel the anti drain back valve built into a spin on filter is restrictive and causes the trans to operate at 185 degrees. i like to get my temps down to 145


Edited by flyingfool
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OK just completed the bypass valve with a stock spin on filter, the anti drain back valve may not be an issue yet, i will run it for 500 miles then cut it open to confirm its filtering...

before the bypass valve i was operating at 185F with the trans thermostat deleted too.  now I'm back where i was after the T-stat delete (135-145 F ) 


the by-pass valve is a piece of brass machined to accept input and output trans cooler lines, prependicular to this, are two 1/4" fittings that feed my remote spin on filter.  inside the brass valve is a bypass hole  of 1/8"  separating the 1/4" npt fitting, and creating a pressure differential for fluid flow. the valve can be Purchased from Frantz FIlters.







Edited by flyingfool
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46 minutes ago, C Dave said:

Sure would be nice if these transmissions came with a spin on filter like the Allison tran does ! Then even a drain plug in the pan. 



the Allison is a by-pass filter, theres no need to drop and drain the pan once you got a spin on.  my current set up cost about $80-90 , but the bypass valve is very important to maintain the trans cooling function , without it it will overheat.

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