PTU Fluid Change D.I.Y.

[twinx1649]

I changed the PTU fluid today and wanted to pass along some lessons learned.

1) It wasn't practical for me to fill the PTU using the fill plug, so I opted to modify the drain plug for fill/drain and it worked well.

2) Modification included drill/tap drain plug for 1/4" NPT to 1/8" NPT fitting and 1/8" NPT plug drilled for safety wire (see pix's).

3) I used Mobil 1 LS 75W-90 synthetic and warm it up first to help it pump easier.

4) Use oil transfer pump with longer 3/16 diameter pick-up tube so it can reach the bottom of the bottle https://www.amazon.com/gp/product/B000BQW5LK/ref=ppx_yo_dt_b_asin_title_o02__o00_s00?ie=UTF8&psc=1

5) Remove exhaust support bracket so you can get both hands in position to remove the fill hose, cover the drain hole after filling, and get the 1/8" plug threaded into the drain plug. I suggest you try this many times with a dry PTU... practice makes perfect... and less clean up.

6) Mark the bottle so you know when you reach the 28 oz. point. I added an additional 1 to 1.5 oz in case I spilled any while performing tube removal after filling. It should be noted that the fill hose had a snug fit into the pipe fitting so it sealed well. I added some electrical tape to the tube in case I needed to create a seal between the tube and fitting (see pix). I also used Permatex thread sealant #59214 (high temperature).

7) Use safety wire on the 1/8" pipe plug to keep everything in place since the installation torque will be lower because you'll be tightening the 1/4" NPT fitting to seat the factory drain plug.

8) Reinstall the exhaust support bracket and add a dab of antiseize to the exhaust bolt for future removal.

 

Note: I recommend changing the fluid every 20K miles, that cat will cook the PTU fluid and changing regularly is cheap insurance. Additionally, I looked at using the PTU vent tube as a fill port, but it was easier to use the drain plug. You can use the vent tube but you can only add 2 oz. at a time until the trapped air in the PTU case is "burped" to allow the fluid to fill. Forcing the fluid with pressure will potentially create a leak path past one of the seals. 

[jkeaton]

Nice write up. 

[TopperHarley]

I am doing this tomorrow thanks so much for idea. 

 

One question, when you pump the fluid in won’t you build up pressure? Aren’t you forcing fluid into a closed sealed unit ? 

 

Im thinking like blowing into a bottle with you mouth, air has no where to go? Am I wrong in thinking this way ?

[2late4u]

i dont have awd but he mentioned this...... You can use the vent tube but you can only add 2 oz. at a time until the trapped air in the PTU case is "burped" to allow the fluid to fill. Forcing the fluid with pressure will potentially create a leak path past one of the seals. 

[Aldlroch]

Where is the fill plug tho ?

[2late4u]

just another reason i dont want an awd vech

[kodiak08]

I am trying to find out what the thread size/pitch is for the PTU drain plug? Thanks in advance.

[TopperHarley]

I used a thread gauge to match up, but for life I can't remember the Tread Pitch......

 

[kejno]

I am also trying to find out what the thread size and pitch is. 

I found something like that:

Fumoto T206N 7/8"-14 UNF Quick Oil Drain Valve

... and I want to replace original drain plug with this drain valve. 

I am not sure about exact size and pitch of the thread... It would be good to know before draining PTU :-) 

[2late4u]

5 hours ago, kejno said:

I am also trying to find out what the thread size and pitch is. 

I found something like that:

Fumoto T206N 7/8"-14 UNF Quick Oil Drain Valve

... and I want to replace original drain plug with this drain valve. 

I am not sure about exact size and pitch of the thread... It would be good to know before draining PTU :-) 

maybe the dealership parts dept could help with this info

[John/Horace]

Adding through the vent is quite easy, just let the car cool down after draining. Warm engine creates venting issues.
 

I was able to add the correct amount in about 10 mins no problem. It doesn’t hold very much fluid.

[kodiak08]

On 3/6/2020 at 7:01 AM, kejno said:

I am also trying to find out what the thread size and pitch is. 

I found something like that:

Fumoto T206N 7/8"-14 UNF Quick Oil Drain Valve

... and I want to replace original drain plug with this drain valve. 

I am not sure about exact size and pitch of the thread... It would be good to know before draining PTU :-) 

 

 

The thread pitch for the PTU drain plug is M20x1.5

[kejno]

9 hours ago, kodiak08 said:

The thread pitch for the PTU drain plug is M20x1.5

 

Thanks for answer! 

So it's a metric thread... I was focused on inches... 

It means that Fumoto F105S or F105N (both M20-1.5) should fit. I will give a try then. 

 

 

On 3/7/2020 at 5:46 AM, John/Horace said:

Adding through the vent is quite easy, just let the car cool down after draining. Warm engine creates venting issues.
I was able to add the correct amount in about 10 mins no problem. It doesn’t hold very much fluid.

 

Do you mean through venting hose? Any special tools required to disconnect it? 

How did you proceed? :-) 

[John/Horace]

No the vent cap just pulls out of the vent hose by hand.

I removed the lower drain plug first and dumped oil, then using a transmission funnel added oil to vent hose to flush a bit.

 

All car systems like automatic  transmission are sealed, so refilling through dipstick needs to be done at room temperature, slowly.

 

The PTU vent hose is 10 times larger than the tranny dipstick, so I found refilling easy. It’s only about two thirds of a quart. Fill funnel 1.5” then lift it out of hose slightly so air can escape as new oil going in, refill funnel 5-6 times after it empties each time.

 

I tried to remove lower heat shield for refill plug access; it’s impossible without wrecking shield and too awkward/time consuming.

My ptu oil was past change interval (used vehicle purchase) at 125k kms, but the oil was not that bad really.

 

 

 

Edited March 11, 2020 by John/Horace

[kejno]

Ok, thanks for clarification. 

 

[TopperHarley]

On 3/6/2020 at 8:46 PM, John/Horace said:

Adding through the vent is quite easy, just let the car cool down after draining. Warm engine creates venting issues.
 

I was able to add the correct amount in about 10 mins no problem. It doesn’t hold very much fluid.

Where is the vent located ?

[John/Horace]

Back of the engine compartment. It’s a rubber  hose you can follow up from the ptu unit.

 

IIRCC I removed part of the plastic intake when I changed the oil.

[TopperHarley]

Great thanks so much. You wouldn’t have a pic of location ? Or using a standard engine bay pic and circling it ? 
 

this would be so easy if I can fill to up here ! 
wonder why they are bringing a breathing tube all the way up there ..... what’s the purpose. 

[John/Horace]

All gear boxes and transfer cases and differentials have a vent because of differential pressure.

Oil and assembly air space heat up with use and would pressurize, forcing oil out through gaskets and seals if not vented.

Usually the vent tube has a small  one way check valve at top to prevent contamination; on jeeps especially they go up high as they can in case anyone plays Uboat captain.

 

I changed the oil two years ago and have no pic. I’m due to change it again in a few weeks, will post a picture then. I’ve never seen it shown on engine bay diagram.

[TopperHarley]

Ok that makes sense. Lol in case someone takes the journey into bayou eh ! Lol 

 

On a side note I went Jiffy Lube and I asked them to change my tranny filter and tranny oil. They said my 2011 journey rt doesn’t have a serviceable tranny filter. ???? And just change tranny  oil That’s it ? 
 

I said let me do some research because I believe all cars have a serviceable tranny filter . What do you guys have to say ?

[14WhiteRTRallye]

 

[2late4u]

18 hours ago, TopperHarley said:

Ok that makes sense. Lol in case someone takes the journey into bayou eh ! Lol 

 

On a side note I went Jiffy Lube and I asked them to change my tranny filter and tranny oil. They said my 2011 journey rt doesn’t have a serviceable tranny filter. ???? And just change tranny  oil That’s it ? 
 

I said let me do some research because I believe all cars have a serviceable tranny filter . What do you guys have to say ?

depends on what engine and trans you have ???? you didnt state what you have...............  also your biggest mistake was going to jiffy lube

Edited April 30, 2020 by 2late4u

[larryl]

Also use Mopar tranny fluid and filter.....

[14WhiteRTRallye]

He stated AWD RT, so 6cyl.

[snosrap]

I was under my Journey today looking for the vent tube and cant find it ... I looked from above.. as asked before can you possible take a pic of the engine bay and roughly show where this tube is as I know mine needs a fluid change bad.