Factory_Tech - How is ATF pumped to radiator/cooler?

[gah]

Factory_Tech or anyone else that knows the answer. How is the ATF pumped around the radiator/cooler circuit? Is there a positive displacement pump in the trans? Also, what kind of pressures are generated in the trans .... 20psi or so? I ask these questions so that I can determine whether an additional inline trans cooler and external ATF filter will put more stress on the pumping mechanism in the trans. The added fluid will be a good thing in terms of temperature, but the additional hoses, filter and cooler will require more work to pump the ATF around. Any help is greatly appreciated. Thanks. ------------------ '00 5.4L AUTO 4X4 F-150 Lariat '98 4.0L 5spd Jeep Wrangler Sport '95 3.8L SC Thunderbird '02 F-350 PSD CC DRW 6SPD 4X4 Lariat (order this year) www.hawthorn-engineering.com

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[Factory_Tech]

The pump works fluid through the transmission, line pressure maxes out at about 170 PSI in the wormtrail but converter out pressure is I think around 15-20 psi. The fluid comes out of the front (converter out) Coolant Bypass Valve fitting (black pipe on the side of the tranny) and if it's warmed up goes to the radiator and tranny cooler then back into the rear fitting on the CBV (rear lube inlet). If the fluid is not up to temp, it runs straight back the black pipe from converter out to rear lube in, (thus bypassing the coolers, hence Coolant bypass valve). External coolers are a great idea, but if you go external filter you need to consider how much resistence the filter gives, and maybe you should talk to a transmission shop about that, I don't really know what works, but I do know that some people are doing it, so a way exists.
hope this helps,

G

[gah]

Thanks Factory_Tech,
the external oil filter is a full flow design and like regular engine oil filters has a built in bypass feature in case the media provides too much resistance. I know that Neal has been using an EF and hasn't had any problems with it.

In Neal's case, the EF may have saved him the cost of a new radiator and cooler. Usually when something in the trans fails, all the crap head straight to the radiator and cooler only to be reintroduced to the trans when the trans is rebuilt. That's why many trans failures are followed by another failure a few months later.

------------------
'00 5.4L AUTO 4X4 F-150 Lariat
'98 4.0L 5spd Jeep Wrangler Sport
'95 3.8L SC Thunderbird
'02 F-350 PSD CC DRW 6SPD 4X4 Lariat (order this year)
www.hawthorn-engineering.com

[Joseangel2001]

Factory_Tech, I'm new to these boards..are you really a Ford tech? If so, can you or one of your fellow techs go to the "Clunking Transmission" board segment and help answer the questions there? I think these boards are great, lots of ideas and useful information.

[Factory_Tech]

I am a tech at Sharonville Transmission Plant, but I work on 4R100s only and the clunk issues are I think 4R70W problems, which I don't know anything about, I've never worked on a 4R70 before. I'll read the thread to see if I do have any ideas, though.

G

[Joseangel2001]

Thanks G...what is the Lariat 4x4 Supercrew..4R70W?