The Diesel Garage banner
1 - 12 of 12 Posts

·
Senior Member
Joined
·
928 Posts
Discussion Starter · #1 ·
I read the book :RTFM: however, it did little more than scare me! "May cause damage" was mentioned quite frequently. Having lost my last truck (Dodge)to transmission problems I'm a bit gun shy. I simply want to drain the tranny and replace the old fluid with a good synthetic. If the sticker under the hood is accurate it was last changed at 75000, so I'm sure it's due.

Ok, so pull the plug, drain and refill with how much of what?

:popcorn:
 

·
MAFIA MEMBER 106
Joined
·
2,262 Posts
if you just drain you will only get 7-8 qts out of the 4r100 (your trans) it holds about 16 qts. so you could have it powerflushed or just change it with regular atf. i change mine every 10000 and every 20000 it gets a filter. this is probably over kill but oil is cheap trannys are not
 

·
Senior Member
Joined
·
928 Posts
Discussion Starter · #3 ·
camojeeper said:
if you just drain you will only get 7-8 qts out of the 4r100 (your trans) it holds about 16 qts. so you could have it powerflushed or just change it with regular atf. i change mine every 10000 and every 20000 it gets a filter. this is probably over kill but oil is cheap trannys are not
I am just looking to drain it and add more until I can do the flush this spring. I was looking at using Mobil 1 Synthetic ATF but after reading the book I'm concerned about mixing with the stock Mercon... should I just use Mercon and wait to do a flush for the Mobil 1?

Im probably just overthinking this, but my Dodge tranny kicked my ***. I would rather not go through that again.
 

·
97F-3504X4PSD
Joined
·
120 Posts
I have read that some guys are recommending against the power flush. It kinda makes sense. If you have crud sitting in low flow areas and try to flush the system, you could push the crud where it can do damage to delicate parts.
 

·
TDG Mafia #95
Joined
·
1,071 Posts
Agreed. I had a thunderbird with 200,000 on the original tranny. Had it powerflushed and within 10,000 it was time for a new tranny. Might have been coincidence, but I don't like it with high mileage trannys.
 

·
Senior Member
Joined
·
206 Posts
So whats the concensus? I want to do mine too. I am trying to decide between flushing, draining the fluid and adding the seven or however much running it half and half, or draining filling, and draining and filling again. What is everyones preferred method?
 

·
Former Ford AutoTrans Eng
Joined
·
169 Posts
There's no such thing as powerflushing. The places that use a machine to change the fluid can't powerflush. There's no way to do that.

The machines use the transmission's pump to push out the old fluid. The old fluid goes to one side of a piston. On the other side of the piston is the new fluid. As the old fluid enters the machine it pushes the piston over, forcing in the new fluid. It goes into the cooler line at the same pressure that the transmission pump is pumping. The notion that this is "powerflushing" and stirring up things in the transmission is an old wive's tale. There isn't even a hint of truth to it.

Here's my preferred method:

http://powerstrokenation.com/forums/showthread.php?t=4338
 

·
Dually Club #3
Joined
·
2,674 Posts
I would also recommend against mixing synthetics with conventional. If you want the mobil then have a shop do the flush and use what ever fluid you want. If you don't want to pay for the flush then use the conventional oil. Mixing different types of fluids is never good.
 

·
Web Wheeler
Joined
·
37 Posts
Just drain the torque converter. Its easy. Undo the pipe plug.

I did add a deep pan, but after a basic drain (no flushing) I was able to put 21L back in. :sly:

I'm sticking with standard Mercon V. $35 for 20L in my part of town. I bought a spin-on filter kit for it too, but I haven't put that on yet. :eek:
 

·
TDG MAFIA #101
Joined
·
390 Posts
Yeah I would not recommend mixing the two fluids either. That would probably spell nothing but trouble.
 

·
MAFIA MEMBER 106
Joined
·
2,262 Posts
just change it aften and get/watch your trany temp gauge.
as i said before every 10000 miles pull the plug and refill w/7-8 qts and be happy oil is cheap .exept that mobil one i do like syn oils but if it has had dino oil you should not mess with it
 
G

·
I have changed my fluid now at least 4 times per the method that Mark K linked to. Its a great and easy flush method...and removes nearly all the old fluid. It sounds scary at first...but if I can do it...trust me...anybody can.

Per fluid...I have gone with Mobil 1 synthetic. It used to be Mercon rated...but now comes Mercon/Mercon V rated. I have enquired and asked around...and with the Mobil stuff anyway...using the dual rated fluid is fine for the 4R100.

I change my fluid every 30k miles. It comes out smelling just like it did going in without a hint of turning brown.

Mark...we sure could use a sticky like that over here. (hint---hint---hint) LOL
 
1 - 12 of 12 Posts
Top