Dexron ATF for trim pump

ChrisCraftFan

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I'm sure this has probably been asked but I can't find it. I replaced my trim cylinders and need to add to the trim fluid. I got the Volvo Penta trim/PS fluid but it is a different color than the fluid in my trim pump. Its red so i am assuming it is ATF fluid. The manual says Dexron ATF can be used but they do not make that anymore. the new Dexron ATF is fully synthetic so I am unsure its is compatible with the older Dexron. I am also not sure what is in there. What is the best fluid to use to fill this pump back up?.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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depending on what year you read the manual, there will be SAE 30, hydraulic oil, ATF, etc. called out

it says dexron as some times the power steering pumps came pre-filled from GM, and dexron would have minimized the required fluid on board as dexron doesnt play nice with type-F (ford) or straight AFT (generally in Chrysler vehicles)

simply drain it, flush it, and use any of the following:

ATF (pick a brand, any brand, just make sure to flush the system a few times when you switch over)
UTF
SAE 30
ISO 32 hyd oil
ISO 46 hyd oil
ISO 64 hyd oil

same goes for your power steering system.

both systems will run on just about anything, and if in a pinch, baby oil or vegetable oil as well.
 

ChrisCraftFan

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I cannot find how to flush this system. Was hoping i didn’t need to. It was not leaking. I was just replacing the hose lines to the trim cylinders and stripped them out, was just hoping to add fluid and bleed it out. It’s a 2000 5.7GSi DP-sm. Manual says VP trim and power steering fluid or Dexron atf. Dexron is no longer available. What is the flushing procedure?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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disconnect the lines at the cylinder, put a bucket underneath to catch, and run fresh fluid in it (both up and down).

now the pump and lines are now flushed

then connect one line at a time to flush the cylinders - for example, with the cylinders retracted, connect the blind end hose only, put the rod end hose in a bucket of fresh oil, and extend the cylinder. the system will draw fresh oil up from the bucket, and the oil oil will be pushed out of the cylinder. at end of stroke, swap hoses, then go the other way. repeat 3 times.

connect your lines

now your whole system is flushed

however your boat would have had Dexron III G (synthetic blend) from the factory which is still available today, you can mix newer dexron fluids (such as Dexron IV, V, or VI), you simply cannot mix to straight ATF because the additives that are in Mobile oil (Dexron) does not play nice with other ATF fluids
 

ChrisCraftFan

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THANKS Scott!!! Glad to hear Dexron III works. It’s much easier to get for sure. I have new cylinders coming so when i get the new manifold block and hoses on i will flush it then. Thanks again. Any idea how much the esteem holds?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Thanks again. Any idea how much the esteem holds?

my guess is you meant system

my second guess is your using talk to text

depends on the reservoir, lines and what is left in the system. a bit more than a quart and a half in the whole system
 

ChrisCraftFan

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Jun 18, 2013
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Thinking i will flush it and put in Dexron VI. That should be available for awhile
 
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