• Welcome to ClassicBroncos! - You are currently viewing the forums as a GUEST. To take advantage of all the site features, please take a moment to register. It's fast, simple and absolutely free. So please join our community today!
    If you have problems registering or can't log into your account, please contact Admin.

4R70W initial fill questions and problems!

latrucker

Contributor
Sr. Member
Joined
Jul 19, 2010
Messages
615
Hoping to get some help from those who have some 4R70W experience. I installed a 4R70W a couple of weeks ago and i think i overfilled it on the initial fill. I added 1 quart to the TC before install and poured about 5 quarts on after install but before i started the engine. Poured in 6 more quarts while idling. Forgot to put my temp sensor in the Derale cooler and pissed out about a quart on the floor before noticed it so a total of 11 quarts at this point taking into account the quart or so i lost. Not even close to full so added until it got close to full mark (to account for fluid expansion) which was another 3 quarts. I am at 14 quarts at this point and not thinking about how much it is going to come up when hot. Took a short drive to warm it up and it did fine except for slightly lazy shifts (half mile round trip) and checked the fluid level, looked fine at the top of full. Took another short drive (fluid temp at 155) and i noticed some slipping in 3rd and OD. Turned around to head back and noticed severe slippage in 3rd and OD with some funny shifts between all gears. Checked level and was 1/8" or better over the full mark. I have a Hughes aftermarket dipstick if it makes a difference. So, obviously I'm overfilled. Today i drained out about 2 quarts of fluid to get it down to 12 quarts total which i understand is the average full amount depending on cooler size. The fluid does not touch the stick when off or running in P when cold. Should i run it until it gets to operating temp even though the fluid isn't touching the stick? Will it get to operating temp without driving it, don't want to ruin the trans. Next question, can overfilling the trans cause it to slip or do I have other issues. Ran and shifted fine when cold, only started slipping when it warmed up. Any help is appreciated and sorry for the long post.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,959
Put fluid in until it at least touches the stick.
Don't know anything about the accuracy of an aftermarket dipstick.
The fluid won't really warm up just idling, after a couple of hours it will be warm but not operating temps. Filled to the bottom of the warm operating temp is generally the middle of the cold fill window.
Is this a used or rebuilt transmission? did you do a valve body kit or anything else inside it? I've had to drop and reinstall a valve body once and never found anything wrong but it fixed a low pressure issue when I first put mine together.
What are you using to control the transmission? Explorer computer, quick shift?
 
OP
OP
latrucker

latrucker

Contributor
Sr. Member
Joined
Jul 19, 2010
Messages
615
Put fluid in until it at least touches the stick.
Don't know anything about the accuracy of an aftermarket dipstick.
The fluid won't really warm up just idling, after a couple of hours it will be warm but not operating temps. Filled to the bottom of the warm operating temp is generally the middle of the cold fill window.
Is this a used or rebuilt transmission? did you do a valve body kit or anything else inside it? I've had to drop and reinstall a valve body once and never found anything wrong but it fixed a low pressure issue when I first put mine together.
What are you using to control the transmission? Explorer computer, quick shift?
Using the Quick Shift 4 and no valve body mods or shift kit. Had the transmission taken apart to install the AA adapter for the D20 and said the trans looked like new so nothing was done but the output shaft and adapter. Just to be clear, your saying fill it not running and cold until it touches the dipstick and drive it until it gets to operating temp and check fluid?
 
OP
OP
latrucker

latrucker

Contributor
Sr. Member
Joined
Jul 19, 2010
Messages
615
Forgot to mention, pressure at idle in park is 52 lbs and high idle is 70 lbs. Is this normal?
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,959
If it is slipping, don't drive. You will kill it fast.
I would be talking with the shop that you had put the output shaft in.
Don't have the pressure specs in front of me.
 
OP
OP
latrucker

latrucker

Contributor
Sr. Member
Joined
Jul 19, 2010
Messages
615
Think I have it fixed, drained 2 quarts and filled very slowly a little at a time and drove between every 1/4 quart that I added. Did this until fluid was at middle of full Range at 175 degrees. Drove and all slippage and funny shifts went away. Started acting silly again after a little drive time and US Shift error code 00-01 came up (range selector). Must have been a combination of fluid level and range sensor. Going to replace range selector on Monday and hopefully all will be good.
 
Top