Hello all,

I want to flush out the tranny before I replace the filter, clean pan and replace gasket.

Is it possible to flush the trans. using the vehicle's trans pump?

I'd do it as such:

Connect one inbound and one outbound line to the tranny,
via short steel lines ( with fittings) and attached neoprene hose leading out to the front of the van.

One hose end goes to an empty 5 gal. bucket.

The other hose goes to an ATF+4 - full 5 gal. bucket.

99, 1500 series, 5.2L, 4sp w/OD

If yes, would I do it in park or in neutral - should it matter?

 

No you can't do it the way you're describing; you will burnout your tranny. The reason you can't do it this way is because there is nothing to "suck" the new fluid back into the tranny.

The cooling lines are a closed system which means that the pressure from the pump forces the fluid out, through the cooler, and back into the tranny. Once you open the system, there is nothing to force the fluid back into the tranny.

 

Hello alloro.
Ahhhhhhh, I see. That's why the quick change places have a pump.

Are there any pumps available to consumers who would like to do it themselves?

Obviously pump pressure is a great consideration.

If the quick change joints would use ATF+4 and change out the filter I'd be more than happy to let them do it. - But they don't.

I've phoned 4 local tranny shops, amazingly 2 of them tell me they use multi trans oils.
The other 2 want about $160 for flush and filter change.

Seems a bit pricy

 

You could try one of those $5 pumps that fit in a drill.

You could always ask the quick change places if you could bring in your own ATF+4 and have them discount their fluid costs from their bill.

 

Yup, I have asked the quick change places and their reply was they cannot drain 'their' fluid out to use mine. I've even offered to pay full price - no discount...they won't do it.

The drill pump idea is worth looking into.

At what pressure does the tranny pump? Any idea ?

Also, what if I were to add trans. fluid through the filler tube at the roughly same rate the old is discharging?

Does the pump draw directly from the pan?
or...
does the pump draw fluid from another location, hence my newly poured in fluid would not reach it in time?

 

Pressure from the pump varies with speed. As a general rule you get 1 PSI per 1 MPH in your highest non-overdrive gear.
The fluid comes from the pan, through the filter, and up the pickup tube to the pump.

This all seems to be a lot of work to accomplish what you're trying to do. A more common solution is to just do a fluid and filter change, plus install an aftermarketdrain plug in the pan while it's out. Run the vehicle for a few miles, then change the fluid again by using the drain plug. This way you're not opening up the tranny again. With the double fluid change, the amount of "old" fluid left in there is minimal at best.

 

If the fluid comes from the pan, it would seem like I could simply add it into the filler tube as it's draining - unless I'm misinterpreting.

Does this sound feasible?

I like the idea of adding a drain plug, although I'm concerned that if I don't get it in right...it'll leak on me.

 

Many of today's tap in drain plugs should be easy to install. The plug itself usually has a plastic self lubricated ring washer like those found ofr the oil pan. When getting such a drain plug, follow the directions for placing on the tranny pan for your given tranny and vehicle. In most cases, the tranny fits a Dodge Truck application.

 

Hi Stev,
Thanks for the info about the drain plug. Looks like I may have to attempt it.

Alloro,
Thanks to you also for your hepl.

 

Yes you could, but you'll have two problems.

1. You have no way to monitor the level in the pan in order to know if you're adding too much fluid, or not enough. If you're planning on running the motor to have the tranny's own pump move the fluid, you're running a big risk of burning out the tranny.

2. This method take considerably more fluid than if you do a drain and refill. The reason for this is the new fluid is mixing with the old fluid as you're adding it. This leaves you with no way of knowing when (or if) all of the old fluid was removed. You could end up pulling a lot of your new fluid out and leaving a lot of the old fluid in. At least withthe drain/refill, then a second drain/refill methodyou can safely assume you've removed at least 95% of the old fluid, probably more.