Im going to be changing my atf on thursday, any tips or pointers on what to do or not to do? ('03 4.0 AT) thanks for the info!

 

drive your truck to warm up the ATF.
remove the fill plug first it will help draining it
then drain plug. when you do that make sure you hold the catch pan up some so it doesn't splash in your eyes.

 

How many miles are on the truck?

I've heard about getting some problems when changing fluid on cars with higher mileage.

 

82,xxx

 

i have 98000 on my truck and i just changed all my fluid (axles, transfer case, transmission) you shouldn't have a problem with changing the fluids if you have keep up with the routine maintenance on your truck.

 

The tranny pan, or torque converter do not have drain plugs.

I just did mine last Saturday, mark a bucket at the 1 gallon point, and pump a gallon out using the cooler lines (engine idling, in park). Shut the engine down, and then add a gallon of new ATF (using dipstick tube). Repeat this until you pump the 4th gallon out, then drop the pan and replace the filter & gasket, being extremely careful to keep clean, to the point of using lint free cloths. By pumping the gallon out, there won't be that much ATF in the pan, but use a tranny pan, because the valve body will drip for awhile.

 

I'm not a fan of the "pumping out" method. I loosen the pan bolts so to tilt the the pan twords what im draining it into. Not that big of a deal, then just drop the whole pan and filter.

for the gasket i usually get stuck with the pos rubber gasket that i put a LIGHT coat of black rtv on. 1 light coat on the pan, stick the gasket on the pan, then 1 light coat over the gasket...then button up. Torque them evenly if you dont have the "feel" quite for tightness.

 

If you just change the ATF in the pan, you are only going to change about 5 quarts of ATF, most of the ATF will be left in the tranny & torque converter. This is why I like the flush method better......Torque spec on the pan bolts is 79-112 INCH/Lbs

 

I've heard this as well when it comes to higher mileage vehicles, especially if you haven't done regular maintenance. I know that I have never serviced the transmission and I'm scared to flush it for fear of messing it up.

I'm sure a pan drop and filter change wouldn't hurt, or flush for that matter, but I just don't want to screw up anything that isn't broken.

 

I see your point , I was just going to do it from a preventative maintenance point of view. I and did hear that about high mileage vehicles, I had 125K on my sonoma and wanted to get it changed and my mechanic said it would probably do more harm then good

you said take the trans cooler line off and let it drain out of there correct and then add a new gallon to it. but you said 4th gallon, according to my owners manual it only takes 10 qts. or am I missing something here? my brothers allison doesnt even take 4 gallons

as you can probably tell, Ive never changed tranny fluid before so Im new to this whole subject

 

im sure he ment 4th quart :)

 

Flushing will screw somthing up, the best way on higher mileage vehicles is to drop the pan and fill it back up.

 

ok, thats what I'll do then

anybody change the transfer case fluid too?

 

Once the cooler lines are disconnected, you start the engine and let it pump the ATF into a bucket....I use 4 gallons as an overkill to make sure the ATF has been replaced in things like the torque converter..

 

Yea i understand...(ASE Master Tech/BMW Level 1 Master Tech). Meanwhile thats what I do with my own vehicles, and have never had a problem doing so.

I also don't have 25 quarts of atf sitting around for a "diy $100 trans flush at home". I'll drop my pan every 30k like I do, and have a happy trans.

 

Yeah Mine was low, and engaged hard ford was going to top it off but I told them to drop it and refil it while where at it. at 92,000

 

I just did mine last friday. Look for a how-to on Monday, im leaving town for the weekend.

 

4 X 4 = 16

 

Okay so it's 20 since you said get the 4th gallon out THEN drop the pan. Glad to see thats all you got out of my post.

 

No, 4 gallons total, it actually took 17 quarts, there was about 1 qt. in the pan when I dropped it......And I also got you change ALL your ATF every 120K miles....30K X 4

 

Just keep doin the redneck trans flush and leave it at that. Your whole math on getting "ALL" the "old" atf magically out by just running it for a second in the trans doesn't hold. Have you ever put ATF in a NEW trans? You'll notice it can take about 2 1/2 gallons or so and fill the pan up properly. By you just running 4 quarts through there lightning fast is no way to guarantee that you're getting "old fluid only" at the cooler....

Converter, cooler(s), cooler lines, clutches, accumulators, shift solenoids and the valve body all are holding. Not just the pan like in your "flush". Now you probably get more old fluid out than just dropping the pan. However since it's a hydraulic fluid, most of it's problem comes from contaminates. Diluting those old contaminantes with fresh fluid in the pan, cleaning the pan and changing the filter is not going to hurt anything. This is not an oil, so when you make it sound like a huge deal that ALL of it gets out at 120k...it's really not a big deal. Oil yes, Hydraulic fluid, No. That is what was recommended LONG before flush machines were around anyway...

 

You just confirmed that just dropping the pan, and only changing that ATF isn't sufficient!!! This is why I use 4 gallons......