LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Automatic Tranny Fluid Flush?

Thread Tools
 
Search this Thread
 
Old Aug 2, 2010 | 11:16 PM
  #1  
mcloud0729's Avatar
Thread Starter
Registered User
 
Joined: May 2010
Posts: 8
Likes: 0
Default Automatic Tranny Fluid Flush?

Hey guys, I was just wondering what I should do about my transmission. It has almost 154,000 miles on the clock and I have no idea when the tranny was serviced last. I'm looking to tune up all aspects of my car before I start really building it, and the transmission is next in line.

Would it be safe to drop the pan and change the filter with such high mileage, or just let it be? What about a full transmission flush? Or would that be playing russian roulette with having the tranny shortly breaking down? Thanks in advance everyone!
Reply
Old Aug 2, 2010 | 11:33 PM
  #2  
ls2pontiac's Avatar
Self-Admitted Scammer
iTrader: (1)
 
Joined: Aug 2007
Posts: 497
Likes: 1
From: Orange County, CA
Default

Drop the pan and change the filter, drive it about 10 miles and then drop the pan again and refill. This will get about 2/3 of the fluid out. Don't do the flush, they usually screw **** up
Reply
Old Aug 2, 2010 | 11:52 PM
  #3  
Cam95Maro's Avatar
On The Tree
iTrader: (1)
 
Joined: Apr 2008
Posts: 181
Likes: 0
From: LaPlata, MD
Default

drop the pan and do it right i have herd the same thing about doing a tranny flush by someplace cause i herd it will actually mess the transmission up idr how but i kno it can
Reply
Old Aug 3, 2010 | 12:44 AM
  #4  
fleetmgr's Avatar
TECH Addict
 
Joined: Jun 2009
Posts: 2,012
Likes: 0
From: Tulsa, OK
Default

Doing a full flush now would be a good idea, and no, in and of itself it won't hurt the tranny. But, it may expose other problems with this kind of mileage. It's supposed to be done every 30k or so. Just make sure that the shop that does has a real flushing machine.
Reply
Old Aug 3, 2010 | 12:59 AM
  #5  
hitmanws6's Avatar
TECH Veteran
iTrader: (20)
 
Joined: Dec 2008
Posts: 4,041
Likes: 5
From: Orange, CA
Default

if the trans has never had a flush i wouldnt do it, we cant do them on cars that have never had one before 100K. Dropping the pan will get some, but not all of the fluid out
Reply
Old Aug 3, 2010 | 08:19 AM
  #6  
blown94's Avatar
On The Tree
iTrader: (1)
 
Joined: Jul 2005
Posts: 122
Likes: 2
Default

yer all missing the all important question here. Whats the condition of the fluid in it now? Is it varnished, burnt, black, brown, red and is the trans experiencing any type of issues right now. If the fluid is already black, forget it, leave it alone, the nails are already in the coffin and the hole has been dug.
Reply
Old Aug 3, 2010 | 12:06 PM
  #7  
killagt's Avatar
TECH Fanatic
iTrader: (3)
 
Joined: Dec 2007
Posts: 1,737
Likes: 2
Default

why not install a drain plug on the pan ? here what I do

Drop pan and change filter with new fluid, install drain plug

next oil change 3k miles or so, take out drain plug and drain out the fluid, fill it back up with new fluid

next oil change, do the same as above, and that it.

FOR THE GOD SAKE , NEVER TAKE YOUR CAR IN THE SHOP FOR COMPLETE FLUSH !, YOUR TRANNY WILL GO OUT NEXT DAY OR SO, AND MOST SHOP REFUSED TO FLUSH ON HIGH MILES TRANNY.
Reply
Old Aug 3, 2010 | 12:50 PM
  #8  
Kota04SXT's Avatar
Teching In
iTrader: (1)
 
Joined: May 2010
Posts: 26
Likes: 0
From: NE Ohio
Default

If you decide to flush it, make sure you find somewhere with a low pressure flush system. High pressure older style flush machines will most likely cause problems. Newer systems are low pressure and take a little out at a time and add a little new at a time and don't cause issues. Pan drop like was said above will only get about 1/4 of the fluid out.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Aug 3, 2010 | 02:53 PM
  #9  
mcloud0729's Avatar
Thread Starter
Registered User
 
Joined: May 2010
Posts: 8
Likes: 0
Default

Thanks for the advice guys! I checked the fluid yesterday and it seems to be pretty brown, doesn't appear to smell burnt though...

The reason I'm looking to change the fluid is because as of lately it feels like the transmission is kind of slipping/lagging when upshifting. I figure changing the fluid and the filter would be the first thing to try, and since it has pretty high mileage I'm not sure how many times if any the previous owner messed with the transmission.
Reply
Old Aug 3, 2010 | 03:06 PM
  #10  
AChotrod's Avatar
11 Second Club
iTrader: (17)
 
Joined: Jul 2008
Posts: 9,896
Likes: 1
From: Chicago area
Default

Originally Posted by hitmanws6
if the trans has never had a flush i wouldnt do it, we cant do them on cars that have never had one before 100K. Dropping the pan will get some, but not all of the fluid out
X2. If its never been changed leave it alone or just top it off. Ive never had good luck with full flushes unless it was done every 30k or so.
Also if your trans is slipping now its not going to help, and will prob make it worse.
Reply
Old Aug 3, 2010 | 04:54 PM
  #11  
fleetmgr's Avatar
TECH Addict
 
Joined: Jun 2009
Posts: 2,012
Likes: 0
From: Tulsa, OK
Default

Originally Posted by mcloud0729
Thanks for the advice guys! I checked the fluid yesterday and it seems to be pretty brown, doesn't appear to smell burnt though...

The reason I'm looking to change the fluid is because as of lately it feels like the transmission is kind of slipping/lagging when upshifting. I figure changing the fluid and the filter would be the first thing to try, and since it has pretty high mileage I'm not sure how many times if any the previous owner messed with the transmission.
Start tranny shopping. No amount of flushing is gonna help you at this point. With the fluid turning brown, it's dead.
Reply
Old Aug 3, 2010 | 05:43 PM
  #12  
Z28Roxy's Avatar
TECH Fanatic
15 Year Member
iTrader: (4)
 
Joined: Mar 2007
Posts: 1,011
Likes: 27
From: Waukesha, WI
Default

I don't believe the stories of all the people who say don't flush it. Just because your cousin's girlfriend's uncle had a trans crap out after it was flushed doesn't mean anything.

I think most of the horror stories are people who already have a slipping transmission and think flushing it will fix things or they see "oh ****, the fluid is black" and flush it. When it craps out they blame the flush, not the previous neglect.

But you can drain it a few times to get most of the fluid out. Or put one trans line in an empty bucket and one in a bucket full of clean trans fluid. lol.
Reply




All times are GMT -5. The time now is 09:03 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE