Trans flush or drop pan?
Thread Starter
Racer
Joined: May 2011
Posts: 346
Likes: 3
Trans flush or drop pan?
Hey all I have a 1985 Vette with 700r4 trans. It has 65k on it and I don't know anything about the maintnance that was done to it. I know the PO didn't drive it hard, hes an old timer. I planned to change out the trans fluid and filter...so today I pulled the dipstick to check it out. The trans fluid is a reddish brown color, more toward red and has a sout smell to it.....not burnt just sour.
What should I do complete flush, Drop pan and change out the filter and fluid, or just leave it alone?
The trans shifts great very positive feel at all speeds and even chirps the tires on the 1-2 shift under moderate accelaration. I don't want to cause any problems but if the fluid is starting to go bad this would probably be the time to catch it with only 65k on the odo.
What should I do complete flush, Drop pan and change out the filter and fluid, or just leave it alone?
The trans shifts great very positive feel at all speeds and even chirps the tires on the 1-2 shift under moderate accelaration. I don't want to cause any problems but if the fluid is starting to go bad this would probably be the time to catch it with only 65k on the odo.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
I would just change the fluid and filter. I have heard some bad things about the flushes causing small openings and channels in the trans to clog up because of all the suspended dirt it kicks up...WW
Thread Starter
Racer
Joined: May 2011
Posts: 346
Likes: 3
OK I went down and pulled the stick again and looked at it in some good lighting. The color is more of a light orangeish to light red it has a sour petrolium smell not a burnt smellFunny guy at the garage I go to said the exact oppisite he told me if he flushes it there will be no problems....if he dous the drop and swap the trans will go.....ok I know he is trying to sell me a service but whats everyones experience?
Melting Slicks
Joined: Nov 2008
Posts: 2,765
Likes: 5
OK I went down and pulled the stick again and looked at it in some good lighting. The color is more of a light orangeish to light red it has a sour petrolium smell not a burnt smellFunny guy at the garage I go to said the exact oppisite he told me if he flushes it there will be no problems....if he dous the drop and swap the trans will go.....ok I know he is trying to sell me a service but whats everyones experience?
The RED DYE has broken down and faded to Orange in color now.
Trans flushes are OK if the trans flush machine has no Power Flush to it.
I mean the type of trans flush that use only the automatic transmission front fluid pump to circulate the old fluid out & New fresh ATF back in.
Definate stay away from Power ATF backflush machines.
Change out the 700 R4 transmission filter too.
It is 1985 original.
Brian
Melting Slicks
Joined: Nov 2008
Posts: 2,765
Likes: 5
I bought my 87 Vert with 32,000 miles on it in 2007.
The ATF was Orange in color too.
I know exactly the funny petroleum smell you are describing.
Be sure to drop the transmission pan & replace the filter.
Trans flush is not 100% necessary.
Changing the 1985 Circa trans filter is 100 % imperative.
I am an ASE Master Mechanic & EX GM Master Mechanic.
I know what I am talking about here on your trans.
BR
The ATF was Orange in color too.
I know exactly the funny petroleum smell you are describing.
Be sure to drop the transmission pan & replace the filter.
Trans flush is not 100% necessary.
Changing the 1985 Circa trans filter is 100 % imperative.
I am an ASE Master Mechanic & EX GM Master Mechanic.
I know what I am talking about here on your trans.
BR
Thread Starter
Racer
Joined: May 2011
Posts: 346
Likes: 3
I bought my 87 Vert with 32,000 miles on it in 2007.
The ATF was Orange in color too.
I know exactly the funny petroleum smell you are describing.
Be sure to drop the transmission pan & replace the filter.
Trans flush is not 100% necessary.
Changing the 1985 Circa trans filter is 100 % imperative.
I am an ASE Master Mechanic & EX GM Master Mechanic.
I know what I am talking about here on your trans.
BR
The ATF was Orange in color too.
I know exactly the funny petroleum smell you are describing.
Be sure to drop the transmission pan & replace the filter.
Trans flush is not 100% necessary.
Changing the 1985 Circa trans filter is 100 % imperative.
I am an ASE Master Mechanic & EX GM Master Mechanic.
I know what I am talking about here on your trans.
BR
Thanks for the quick reply I will call around and find if anyone does the trans pump swap. If not I will do the drop and swap asap. By the way nice avatar I LOVE T/A's
Drifting
Joined: Aug 2006
Posts: 1,624
Likes: 2
From: Canandaigua New York
Dropping the pan and changing the filter will not get all the old fluid out.
There will still be some left in the torque converter.
If the trans shifts fine with no problems, then the best way would be to disconnect the high pressure line from the radiator and stick it in a 5 gallon bucket. (attach a rubber hose)
Start the car and let the fluid drain until the fluid starts to 'sputter' coming out.
Shut off the engine.Refill with about 4 quarts of tranny fluid and do it again. Keep doing it until the fluid looks clean and red.
Reconnect the line to the radiator and refill.
If you are not smelling anything 'burnt' from the tranny, chances are there isn't anything floating around inside and the filter is probably fine.
If you still don't feel comfortable after doing it this way, you can still drain the pan and install a new filter knowing that you got all of the old fluid out of the torque converter too.
There will still be some left in the torque converter.
If the trans shifts fine with no problems, then the best way would be to disconnect the high pressure line from the radiator and stick it in a 5 gallon bucket. (attach a rubber hose)
Start the car and let the fluid drain until the fluid starts to 'sputter' coming out.
Shut off the engine.Refill with about 4 quarts of tranny fluid and do it again. Keep doing it until the fluid looks clean and red.
Reconnect the line to the radiator and refill.
If you are not smelling anything 'burnt' from the tranny, chances are there isn't anything floating around inside and the filter is probably fine.
If you still don't feel comfortable after doing it this way, you can still drain the pan and install a new filter knowing that you got all of the old fluid out of the torque converter too.
Last edited by Keystring; May 26, 2011 at 10:56 AM.
Team Owner
Joined: Jul 2004
Posts: 28,369
Likes: 3,258
From: Hartford WI
Not flushing fluid is an old wives tale perpetuated by 2 groups of people.
1. The shop. They don't want to work on your "Hail Mary" trans restoration because they know that when it breaks, you will blame them.
2. People who have no real science behind it.
1. The shop. They don't want to work on your "Hail Mary" trans restoration because they know that when it breaks, you will blame them.
2. People who have no real science behind it.
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Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
Scared of spilling the pan?
Go to Home depot and buy a $10 drill pump and some 1/4" hose with the appropiate fittings to connect to the pump. Get a lenght of discharge hose...1/2".
Stick the small hose down the dip stick hole, suck out the fluid, then drop the pan and change the filter.
Refill trans and start up. Suck it out again.
refill and drive. This DIY method gets close to 75% of the old stuff out without a mess.
Go to Home depot and buy a $10 drill pump and some 1/4" hose with the appropiate fittings to connect to the pump. Get a lenght of discharge hose...1/2".
Stick the small hose down the dip stick hole, suck out the fluid, then drop the pan and change the filter.
Refill trans and start up. Suck it out again.
refill and drive. This DIY method gets close to 75% of the old stuff out without a mess.
Drifting
Joined: Oct 2006
Posts: 1,328
Likes: 14
From: Stafford Connecticut
Have your trans flushed then change your filter.You could also install a trans pan with a magnetic drain plug.Don't forget you have a magnet in the bottom of your trans pan that needs to be cleaned.
Le Mans Master
Joined: May 1999
Posts: 6,513
Likes: 1,301
From: Windermere FL
Here is how I do it. Messy.
1. Remove dip stick.
2. Use hand pump or drill powered pump and remove as much fluid from the dip stick as you can get out.
3. Refill with fresh fluid
4. Remove the coolant line at the radiator - I forget which one. Put a coupler with a longer hose into a 5 gallon bucket. Mark the bucket with the number of quarts you managed to put in step 3.
5. Crank the car and make sure you got the right hose. If not switch.
(there is the mess)
6. Have a friend let the car run until the bucket is about a quart or two under your mark. Shut off the engine.
7. Refill and repeat until fluid comes out fresh. Usually about 10-12 quarts is needed.
1. Remove dip stick.
2. Use hand pump or drill powered pump and remove as much fluid from the dip stick as you can get out.
3. Refill with fresh fluid
4. Remove the coolant line at the radiator - I forget which one. Put a coupler with a longer hose into a 5 gallon bucket. Mark the bucket with the number of quarts you managed to put in step 3.
5. Crank the car and make sure you got the right hose. If not switch.
(there is the mess)
6. Have a friend let the car run until the bucket is about a quart or two under your mark. Shut off the engine.
7. Refill and repeat until fluid comes out fresh. Usually about 10-12 quarts is needed.
Melting Slicks
Joined: Nov 2008
Posts: 2,765
Likes: 5
We all have c4's.
My 70 TA is sleek & sexy like a C4 but old School Kool too.
Has the wrap around Thin chrome bumper too unique to the early birds & T/A's.
BR
