What are the common leak points on the 2008 Impala Transmission? - Chevy Impala Forums
8th Gen Drivetrain Transmissions, clutches, and axles.

User Tag List

 2Likes
  • 1 Post By tlucas
  • 1 Post By retiredpauly
 
LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 12-29-2016, 09:31 AM Thread Starter
Junior Member
 
tlucas's Avatar
 
Join Date: Dec 2016
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Thanks: 0
Thanked 1 Time in 1 Post
What are the common leak points on the 2008 Impala Transmission?

Hello. I just purchased a 2008 Impala that is leaking tranny fluid from various locations. I replaced both cooler lines and fittings at the transmission, new gasket and filter kit, and a new fill tube seal/grommet. I still have a leak that appears to be coming from above and it's collecting on the pan gasket, making it appear as if the pan gasket is leaking. I checked the vent and it is open and working fine. I checked both axle seals and looked at torque seal through the inspection plate. All are dry. I put vehicle on the lift while running and wheels spinning, and no leak. It only leaks while driving/under load, with tranny at operating temperature. It runs down from somewhere, collects on the pan, and the aluminum frame behind the pan, and blows back on the converter, and most of the way back on the underneath of car. I can't tell where else the fluid may be leaking from and I'm wondering what other leaks are common on these transmissions? Thanks.
shooter_tx likes this.
tlucas is offline  
The Following User Says Thank You to tlucas For This Useful Post:
shooter_tx (12-29-2016)
Sponsored Links
Advertisement
 
post #2 of (permalink) Old 12-30-2016, 07:05 AM
Administrator

 
retiredpauly's Avatar
 
Join Date: Jan 2012
Location: Cochrane Alberta Canada
Posts: 9,411
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 69 Post(s)
Thanks: 1,268
Thanked 2,275 Times in 1,291 Posts
First off
Welcome to the forum.

It almost sounds as if it's been over filled. Perhaps when you did the service on it you may have put too much in? I know the owner manual ( or someplace I read it ) says that after its HOT it must sit for a couple minutes under idle to check for the proper level.

Other than what you have replaced and repaired already, and it's not leaking from the main gasket that goes between the outer portion of the transmission not really sure where it can come from.
tlucas likes this.

Some things are better left unsaid, which I generally realize right after I have said them.
retiredpauly is offline  
post #3 of (permalink) Old 12-30-2016, 08:21 AM Thread Starter
Junior Member
 
tlucas's Avatar
 
Join Date: Dec 2016
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Thanks: 0
Thanked 1 Time in 1 Post
Thanks for the welcome. The thought of overfilling crossed my mind. I have wondered whether or not the dipstick is accurate. When I first got the car, there was no fluid at all showing on the dipstick with a warm transmission at idle. It took approx 5 quarts to bring it to proper level according to the dipstick. I may have overfilled it at this point. I wasn't expecting to use 5 quarts just to top it off. It was after this that I dropped the pan, changed the filter and gasket. It took approx 7 quarts to refill, according to the dipstick. Does 7 quarts sound like the right amount to put in after a pan drain and filter change? I don't have an owners manual. The last thing I did was replace the fill tube grommet, as it appeared to be coming from there. When I had the fill tube out, I looked in there with a mirror, and the fluid level was right at the top of the fill tube hole. When I pushed the new rubber grommet in, fluid pushed out, so it appears to be full--maybe too full. Currently, I'm still getting significant dripping to the point of blowing back on the exhaust while driving, however, the dipstick is showing that I need approximately 1/2 quart just to get me into the crosshatch, or 1 quart to get me to the top end of operating range. With engine shut off and tranny cold, fluid level shows over full, near the bend in the dipstick. If I am overfull, the dipstick is not reflecting that. Guess I just drive it and keep and eye on things. Thanks for the reply, and any more tips relative to this update, are welcome. Thanks again!
tlucas is offline  
 
post #4 of (permalink) Old 12-30-2016, 11:15 AM
Junior Member
 
shooter_tx's Avatar
 
Join Date: Nov 2008
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 1
Thanked 0 Times in 0 Posts
What are the common leak points on the 2008 Impala Transmission?

Quote:
Originally Posted by tlucas View Post
Guess I just drive it and keep and eye on things. Thanks for the reply, and any more tips relative to this update, are welcome. Thanks again!
I would personally NOT 'just drive it' under these conditions... maybe try to score a year-appropriate fill tube and dipstick off of eBay (from a reputable seller, of course) or an automotive website?

By the way... if you're an Amazon user, you can add your vehicle to your Amazon Garage and find year- and model-appropriate replacement parts. That's how I got replacement headlamps for my 2005 Impala for $90.

Edit:




Sent from my iPad using Tapatalk
shooter_tx is offline  
post #5 of (permalink) Old 01-05-2017, 11:01 AM
Senior Member
 
hatzie's Avatar
 
Join Date: Nov 2009
Location: Wentworth, NH & Cincinnati, OH
Posts: 391
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Thanks: 42
Thanked 85 Times in 71 Posts
You'll have a fire if it's blowing out on the exhaust.
Common automatic transmission leak points are the pan gasket, cooler lines, input seal, and output seals. The 4T65E has an end cover on the LH end of the transmission too. As long as you're using the original gaskets the pan and side cover usually don't leak. If it's coming out around the dipstick tube with a new seal it's probably overfilled.

The original AC Delco GM 24206182 steel core 4T65E pan gasket is right around $30. It's reusable multiple times and it doesn't leak. I hope you or the previous owner didn't put it in the bin. The gaskets that come with the strainer, what you're calling a filter, should be put directly in the trash bin. They will not seal like the OEM gasket.

Transmission fluid levels aren't checked like motor oil... with the engine off. They need to be checked with the fluid warmed up in PARK with the engine running. The dipstick usually says how it should be done.

If you have it overfilled it'll aerate the fluid and cause other issues.

Did you replace refrigerator magnet that GM originally installed in the pan on your 4T65E with high temp magnets following the instructions in GM TSB 08-07-30-040C?

Did you check it with the engine running, in PARK, and the transmission up to temp?

Did you use Dexron VI? If you used fluid claiming to be Dexron III or some other transmission fluid you need to get it out of that transmission ASAP and refill with Dexron VI.
Dexron VI is Dexron VI... It doesn't have to be GM AC Delco branded Dexron VI as long as the bottle says Dexron VI and not "Dexron VI compatible". WalMart Supertech Dexron VI is fine. Draining, re-filling, running the engine til the trans is hot and draining again... twice... should dilute the remaining Dexron III, on the third fill with Dexron VI, to the point that it won't hurt much.

2009 Impala SS
"Speed never killed anyone. Suddenly becoming stationary... that's what gets you." Jeremy Clarkson

Last edited by hatzie; 01-05-2017 at 12:27 PM.
hatzie is offline  
post #6 of (permalink) Old 01-05-2017, 11:23 AM
Member
 
reubenswinks's Avatar
 
Join Date: Nov 2014
Location: Grand Haven, MI
Posts: 75
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Thanks: 13
Thanked 10 Times in 9 Posts
Quote:
Originally Posted by tlucas View Post
It took approx 7 quarts to refill, according to the dipstick. Does 7 quarts sound like the right amount to put in after a pan drain and filter change?
This sounds right. I believe I put around 7.5 quarts in after I dropped the pan and did the filter on my transmission. If you put that amount in and the dipstick shows that as being correct, sounds like that is good to go. Like others said, must check level with fluid hot, and vehicle running.
reubenswinks is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevy Impala Forums 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 email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Transmission line leak chevynut1 8th Gen Drivetrain 7 01-10-2015 05:29 PM
HELP! - 2008 Impala 3.5 Transmission Leak dswenson86 Chevy Impala 8th Gen Discussion 1 12-05-2014 09:05 AM
Transmission Leak? Thrasher Chevy Impala 8th Gen Discussion 9 04-27-2014 05:40 PM
Transmission line leak aztecs2006 7th Gen Drivetrain 11 06-03-2013 07:46 PM
Transmission Leak RyanZ17 Chevy Caprice 7 10-14-2010 06:59 AM

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 On
Pingbacks are On
Refbacks are On

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