Adjusting auto tranny fluid pressure

[GasSavers_RoadWarrior]

What should firm up anything is putting a bottle of "Lucas Transmission Fix" in it. Or changing out the fluid for Universal Tractor Fluid.

Line pressure on hydraulic automatics usually has something to do with the governor so a valve associated with that with a screw adjustment is probably the line pressure.

Shift overlap may be controlled by an accumulator, blocking it off may de-slush it.

This is how we do it on a Chrysler 3 speed transaxle (A404, A413, A470, A670, 30TH, 31TH) ...
http://members.firststep.net/stevien.../valvebod.html

[COMP]

Type F ups the pressure

[Jay2TheRescue]

Originally Posted by COMP

Type F ups the pressure

But don't mix type F with other types... I've heard that's bad. I know a guy that runs type F in all of his cars and trucks. He says the transmissions last longer too.

[GasSavers_RoadWarrior]

My understanding of the sitch is...

Type F has friction modifiers that make clutch packs grab harder, doesn't necessarily increase line pressure but may give better performance on some trannies.

Type F mixes fine with regular ATF if you don't need that much extra grab 1 quart in a normal fill is plenty for most folks, BUT if you put anything but type F in a tranny that NEEDS it, it will slip like hell and go nowhere.

[COMP]

Originally Posted by RoadWarrior

My understanding of the sitch is...

Type F has friction modifiers that make clutch packs grab harder, doesn't necessarily increase line pressure but may give better performance on some trannies.

Type F mixes fine with regular ATF if you don't need that much extra grab 1 quart in a normal fill is plenty for most folks, BUT if you put anything but type F in a tranny that NEEDS it, it will slip like hell and go nowhere.

ATF + has the modifiers in it

[Jay2TheRescue]

Originally Posted by RoadWarrior

My understanding of the sitch is...

Type F has friction modifiers that make clutch packs grab harder, doesn't necessarily increase line pressure but may give better performance on some trannies.

Type F mixes fine with regular ATF if you don't need that much extra grab 1 quart in a normal fill is plenty for most folks, BUT if you put anything but type F in a tranny that NEEDS it, it will slip like hell and go nowhere.

So if you have a slipping tranny you can make due for a short time with type F? If so I should have done that with my old Pontiac wagon. That was starting to slip by the time we got rid of it.

-Jay

[GasSavers_RoadWarrior]

Yeah, it's been known to work. However, that "Lucas Transmission Fix" also does the job. Had a Tempo in the family with the ford ATX it was slipping, was a 200,000+ mile tranny, Transmission fix held up for 2 years and another 50,000 miles. However, if you do this BEFORE it starts slipping, you help the frictions live wayyyyyyy longer, and it also runs cooler, because the quicker grab means less heat as things mash together, due to shortening the time they're grinding against each other. For an example of that, stand a bike upside down and spin the wheel, first stop it by slowly applying pressure to the tire with your thumb, probably gets too hot to bear before you stop it, whereas if you jab your thumb into the tire hard, you stop it while only feeling a brief flush of heat on your thumb. (Make sure there's no sharp bits of gravel or glass shards stuck in the tire before you try this)

[COMP]

Originally Posted by Jay2TheRescue

So if you have a slipping tranny you can make due for a short time with type F? If so I should have done that with my old Pontiac wagon. That was starting to slip by the time we got rid of it.

-Jay

add the + (atf plus)

[Hoopster]

Is the Lucas transmission fix compatible with synthetic fluid?

[GasSavers_RoadWarrior]

Don't know, but if you've got a transmission that needs a special synthetic like Mercon V or a 7176, ATF +4 spec fluid, then don't mess with it. If it takes regular ATF, then it's probably not so fussy.

Actually if you're using a synthetic "just because" you might want to try some of the synthetic chrysler ATF +4 which has larger amounts of friction modifiers than "regular", then at least you're blending synthetics.