Radiator wrong tranny oil flow? - JeepForum.com
 9Likes
Reply
 
LinkBack Thread Tools
post #1 of 19 Old 02-15-2020, 12:50 PM Thread Starter
ZblackliZard
Registered User
 
ZblackliZard's Avatar
1993 ZJ 
 
Join Date: Aug 2019
Posts: 62
Garage
Radiator wrong tranny oil flow?

Hello guys,

So i recently had to rebuild my transmission due to burnt clutch disk however the previous owner had it rebuilt less than a year ago. A little before having the issue with my transmission i changed my radiator. I'm a bit new to auto transmission so that might sound stupid first i noticed no oil came out of the oil lines is that normal? and could i have mistakenly connected the wrong line to the wrong connection ( feed to return and vice versa)?

Thanks in advance

ZblackliZard is offline  
Sponsored Links
Advertisement
 
post #2 of 19 Old 02-16-2020, 07:03 PM
zjosh93
Registered User
1993 ZJ 
 
Join Date: Aug 2010
Location: Austin
Posts: 2,921
Flow from the front of the trans should go to the bottom of the cooler. That way it purges out any air bubbles. Not sure it would have killed an otherwise good trans.

From what I've seen though a lot of trans places do the minimum required to get the trans out of warranty.
wildbill23c and ZblackliZard like this.
zjosh93 is offline  
post #3 of 19 Old 02-17-2020, 08:39 AM
Mr. Puddles
Senior Member
1996 ZJ 
 
Join Date: Mar 2018
Location: Little Elm
Posts: 700
Garage
Quote:
Originally Posted by ZblackliZard View Post
i noticed no oil came out of the oil lines is that normal??
Make sure I understand what you are saying..

When you disconnected the trans cooler lines from the radiator you had no fluid come out. Is that correct?
ZblackliZard likes this.

Follow the build!

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


2002 Dakota aka Winnie aka Mad Max
1996 Grand Cherokee aka Puddles aka Pikey Life
Quote:
Originally Posted by kg6mov View Post
The 4.0 is dumb old tractor motor, itís too stupid to know itís supposed to die.
Mr. Puddles is offline  
 
post #4 of 19 Old 02-17-2020, 09:24 AM Thread Starter
ZblackliZard
Registered User
 
ZblackliZard's Avatar
1993 ZJ 
 
Join Date: Aug 2019
Posts: 62
Garage
Quote:
Originally Posted by Mr. Puddles View Post
Quote:
Originally Posted by ZblackliZard View Post
i noticed no oil came out of the oil lines is that normal??
Make sure I understand what you are saying..

When you disconnected the trans cooler lines from the radiator you had no fluid come out. Is that correct?
Correct.
ZblackliZard is offline  
post #5 of 19 Old 02-17-2020, 11:31 AM
Mr. Puddles
Senior Member
1996 ZJ 
 
Join Date: Mar 2018
Location: Little Elm
Posts: 700
Garage
Quote:
Originally Posted by ZblackliZard View Post
Correct.
Ok so in my mind the first most likely issue is low fluid level in the trans (which would match up with a premature failure of the trans). The next option would be that the lines are plugged somewhere close to the trans. Id say thats highly unlikely but it all depends on the quality of the tech that installed the trans after the last rebuild (the shop that did mine gave me a GM dipstick and tube then claimed I did it.). When you pulled the trans out how much fluid did you get out of it?
ZblackliZard likes this.

Follow the build!

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


2002 Dakota aka Winnie aka Mad Max
1996 Grand Cherokee aka Puddles aka Pikey Life
Quote:
Originally Posted by kg6mov View Post
The 4.0 is dumb old tractor motor, itís too stupid to know itís supposed to die.
Mr. Puddles is offline  
post #6 of 19 Old 02-17-2020, 12:44 PM Thread Starter
ZblackliZard
Registered User
 
ZblackliZard's Avatar
1993 ZJ 
 
Join Date: Aug 2019
Posts: 62
Garage
Quote:
Originally Posted by Mr. Puddles View Post
OK so in my mind the first most likely issue is low fluid level in the trans (which would match up with a premature failure of the trans). The next option would be that the lines are plugged somewhere close to the trans. Id say that's highly unlikely but it all depends on the quality of the tech that installed the trans after the last rebuild (the shop that did mine gave me a GM dipstick and tube then claimed I did it.). When you pulled the trans out how much fluid did you get out of it?
I did not do the rebuild however as of what i saw they got a pan of around 50cm diameter at like 5-10 cm height. i did dipstick it beforehand though and it was a bit higher than recommended level. I am adding an auxiliary radiator soon, so i understand when i unplug the lines i should get oil spill out now or this would mean the lines are clogged? and while i got you there should i add the auxiliary radiator before or after the main one or it doesn't matter?
Thanks for your help!
ZblackliZard is offline  
post #7 of 19 Old 02-17-2020, 01:11 PM
Mr. Puddles
Senior Member
1996 ZJ 
 
Join Date: Mar 2018
Location: Little Elm
Posts: 700
Garage
Quote:
Originally Posted by ZblackliZard View Post
I did not do the rebuild however as of what i saw they got a pan of around 50cm diameter at like 5-10 cm height. i did dipstick it beforehand though and it was a bit higher than recommended level. I am adding an auxiliary radiator soon, so i understand when i unplug the lines i should get oil spill out now or this would mean the lines are clogged? and while i got you there should i add the auxiliary radiator before or after the main one or it doesn't matter?
Thanks for your help!
When you checked it was the vehicle running? To get accurate measurement I believe it needs to be warm, running, and in Neutral.

If you unplug the lines and nothing comes out it sounds like the lines are clogged or they bypassed the cooler with some sort of hose. Without being able to actually crawl under it and look its tough to tell for sure.

As far as adding a secondary cooler...


Based on what I have seen from other users on here that have done so they added it after (or in place of) the built in trans cooler. The built in cooler is helpful if you live in colder climates as it helps to warm the trans up quicker. Down side is it can also add heat to the trans fluid if the radiator gets excessively hot. Another down side (and the primary reason I plan to completely bypass the radiator) is the possibility that the cooler can leak and allow coolant into the trans (pretty much a death sentence).

Follow the build!

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


2002 Dakota aka Winnie aka Mad Max
1996 Grand Cherokee aka Puddles aka Pikey Life
Quote:
Originally Posted by kg6mov View Post
The 4.0 is dumb old tractor motor, itís too stupid to know itís supposed to die.
Mr. Puddles is offline  
post #8 of 19 Old 02-18-2020, 04:05 PM Thread Starter
ZblackliZard
Registered User
 
ZblackliZard's Avatar
1993 ZJ 
 
Join Date: Aug 2019
Posts: 62
Garage
Quote:
Originally Posted by Mr. Puddles View Post
When you checked it was the vehicle running? To get accurate measurement I believe it needs to be warm, running, and in Neutral.

If you unplug the lines and nothing comes out it sounds like the lines are clogged or they bypassed the cooler with some sort of hose. Without being able to actually crawl under it and look its tough to tell for sure.

As far as adding a secondary cooler...


Based on what I have seen from other users on here that have done so they added it after (or in place of) the built in trans cooler. The built in cooler is helpful if you live in colder climates as it helps to warm the trans up quicker. Down side is it can also add heat to the trans fluid if the radiator gets excessively hot. Another down side (and the primary reason I plan to completely bypass the radiator) is the possibility that the cooler can leak and allow coolant into the trans (pretty much a death sentence).
So you're saying bypassing completely the radiator would be better to keep my trans cool? I don't think the cooler is bypassed by some hose, the lines must be clogged (or could it be the oil pump?) anyway i drove it for like 200miles since i got it rebuilt could i have killed it again (i did not check on the flow again)?
ZblackliZard is offline  
post #9 of 19 Old 02-18-2020, 04:17 PM
Mr. Puddles
Senior Member
1996 ZJ 
 
Join Date: Mar 2018
Location: Little Elm
Posts: 700
Garage
Quote:
Originally Posted by ZblackliZard View Post
So you're saying bypassing completely the radiator would be better to keep my trans cool? I don't think the cooler is bypassed by some hose, the lines must be clogged (or could it be the oil pump?) anyway i drove it for like 200miles since i got it rebuilt could i have killed it again (i did not check on the flow again)?
Bypassing the radiator depends on where you live. If you are in a hotter climate (such as the desert) then yes its generally easier on the trans to bypass it. I notice your avatar pic has a euro style plate on it. Where do you live?

If the pump is not working then you wouldnt have transmission function. We need to figure out where the flow blockage is. Pull the rubber hose off the metal line by the radiator. If you dont get any fluid move closer to the trans and see if there is any other rubber line. If so disconnect that and see if you have fluid. If not maybe @Timo_90xj can chime in and say if the metal lines can be pulled off the trans or not.

Follow the build!

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


2002 Dakota aka Winnie aka Mad Max
1996 Grand Cherokee aka Puddles aka Pikey Life
Quote:
Originally Posted by kg6mov View Post
The 4.0 is dumb old tractor motor, itís too stupid to know itís supposed to die.
Mr. Puddles is offline  
post #10 of 19 Old 02-19-2020, 03:26 AM Thread Starter
ZblackliZard
Registered User
 
ZblackliZard's Avatar
1993 ZJ 
 
Join Date: Aug 2019
Posts: 62
Garage
Quote:
Originally Posted by Mr. Puddles View Post
Bypassing the radiator depends on where you live. If you are in a hotter climate (such as the desert) then yes its generally easier on the trans to bypass it. I notice your avatar pic has a euro style plate on it. Where do you live?

If the pump is not working then you wouldnt have transmission function. We need to figure out where the flow blockage is. Pull the rubber hose off the metal line by the radiator. If you dont get any fluid move closer to the trans and see if there is any other rubber line. If so disconnect that and see if you have fluid. If not maybe @Timo_90xj can chime in and say if the metal lines can be pulled off the trans or not.
So i live in Lebanon but i drive her mostly off-road on the snow. As you may have noticed it is on 33 inch tires, may get 35's in the future. I'll try to check the fluid later on today and i'll get back to you with whatever i find.
ZblackliZard is offline  
post #11 of 19 Old 02-19-2020, 03:29 AM Thread Starter
ZblackliZard
Registered User
 
ZblackliZard's Avatar
1993 ZJ 
 
Join Date: Aug 2019
Posts: 62
Garage
there is something that's bugging me though. I thought adding an auxillary radiator in addition to the one built in would be the best way to cool my transmission. How is bypassing the main radiator gonna give me more cooling?
ZblackliZard is offline  
post #12 of 19 Old 02-19-2020, 04:32 AM
Zilliver
Registered User
1998 ZJ 
 
Join Date: Sep 2015
Location: Vantaa <-> Tallinn
Posts: 555
The main radiator will get hot - engine coolant will heat it up, the external one will not. So if you only use the external, it will be cooler.

Only thing to think about is if you live in the cold climate, the main radiator will not help to warm up the tranny oil, so your transmission will take a lot longer to be at the operating temperature.
Timo_90xj and ZblackliZard like this.

98 Grand Cherokee 5.9 - daily
95 Grand Cherokee 5.2 - offroad
Zilliver is offline  
post #13 of 19 Old 02-23-2020, 02:48 AM
Timo_90xj
Web Wheeler
 
Timo_90xj's Avatar
1998 ZJ 
 
Join Date: Mar 2006
Location: Helsinki, Finland - on the European side of the Atlantic
Posts: 10,287
On cooler climates bypassing the radiator will result in slow warm-up and also may cause tranny to be too cold in very cold temps. In-line fluid thermostat between cooler supply and return lines is the best solution to that issue.

wildbill23c likes this.

1998 Grand Cherokee 5.9 LX daily driver, 1.75" BB, 32" KM2s, HPD30 Eaton e-locker/D44a stock LSD, 4.56 gears, custom- fabbed tube bumpers and tube fenders,...


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.



1990 XJ Limited (4-door), 4.0 I6, AW4, NP242, ***rolled and totalled @ 165k miles***

***Under construction***
1990 XJ (4-door), 4.0 I6, AW4, NP242, PBR 42" tires, Unimog 404 portal axles, 110" WB, full cage + uniframe completely rebuilt, front 3-link + panhard / double triangulated 4-link rear,... ***SOLD***
Timo_90xj is offline  
post #14 of 19 Old 02-23-2020, 09:21 AM Thread Starter
ZblackliZard
Registered User
 
ZblackliZard's Avatar
1993 ZJ 
 
Join Date: Aug 2019
Posts: 62
Garage
The coolest it gets here in lebanon is like -5 Celsius so I don't think it qualifies as cooler climate. I think I'll go with the aux radiator. Thanks anyway guys
ZblackliZard is offline  
post #15 of 19 Old 02-23-2020, 08:45 PM
AlamoJeeper
Senior Member
 
AlamoJeeper's Avatar
1995 ZJ 
 
Join Date: Jul 2015
Location: San Antonio
Posts: 543
The in radiator tank transmission cooler is on the cool side of the radiator. The engine coolant temperature gauge sensor is on the hot side of the radiator. The coolant on the cool side of the radiator goes to the water pump to be pumped through the engine. That is what cools the engine. So the transmission fluid is deliberately put in the cool side of the radiator.

Like Timo says, a thermostat bypass between the transmission and the cooler(s) at the front of the vehicle is the best solution. And like those braided lines and AN fittings.

It will help us help you if you include your Jeep's year, engine, and other particulars in your profile. Also location. If you don't want to be specific on your location, you can include your state, province, or country if it is a smaller country.
AlamoJeeper is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome