Flushing Synthetic from TH-350
Thread Starter
Racer
Joined: Jul 2004
Posts: 400
Likes: 1
From: California
Flushing Synthetic from TH-350
Is there anything special i need to do to flush synthetic from my tranny? i put that Amsoil stuff in thinking it would be ok in a 30yr old tranny...big boo boo 
can a shop flush it for you or do you have to take the converter out also.
can a shop flush it for you or do you have to take the converter out also.
Melting Slicks
Joined: Jul 2002
Posts: 3,000
Likes: 22
From: Boulder Creek California
I think the HP Books TH350 book talks about flushing it, check it out at a bookstore first though. The cooler alone is easy enough, just buy a can of cooler flusher.
If you want a shop to do it, any jippy lube or better can do that.
If you want a shop to do it, any jippy lube or better can do that.
Drifting
Joined: Jan 2002
Posts: 1,957
Likes: 0
From: Chico Ca
I once read how synthetic oil in a tranny ruins it because the clutches slip too much and they used to grab a little better with regular fluid. Flush it with regualr tranny fluid run it drain it run it drain it.
Thread Starter
Racer
Joined: Jul 2004
Posts: 400
Likes: 1
From: California
Originally Posted by Love My 72 and 77
I once read how synthetic oil in a tranny ruins it because the clutches slip too much and they used to grab a little better with regular fluid. Flush it with regualr tranny fluid run it drain it run it drain it.
Team Owner
Joined: Sep 2003
Posts: 88,393
Likes: 2
From: eville in
Originally Posted by EVIL_GRIM
ya know what, i noticed waaay more shavings in my pan fater i put the synthetic in, and that was after like the 4th gasket and fliter change, lol. i'd have to agree with you on that one. hmmm, do you have to take theTorque converter out to flush the entire system? or can it be done by a shop without having to give them lots of $$$
Thread Starter
Racer
Joined: Jul 2004
Posts: 400
Likes: 1
From: California
well, it accelerates better then it did when i have m filter changed, but when i first put synthetic in, it would take longer to shift tot he next gear, meaning it would rev higher and i had to slow down so it could shift, but after awhile it shifted fine, but i think that high reving shift was due to the vaccum line being off the modulator thing on the tranny, i put it on then it stopped, lol. but when it wouldnt stop leaking, i dropped the pan and saw just about as much shavings as when i first dropped the pan, and i can bet that hadnt been dropped in YEARS! 
Team Owner
Joined: Sep 2003
Posts: 88,393
Likes: 2
From: eville in
Originally Posted by EVIL_GRIM
well, it accelerates better then it did when i have m filter changed, but when i first put synthetic in, it would take longer to shift tot he next gear, meaning it would rev higher and i had to slow down so it could shift, but after awhile it shifted fine, but i think that high reving shift was due to the vaccum line being off the modulator thing on the tranny, i put it on then it stopped, lol. but when it wouldnt stop leaking, i dropped the pan and saw just about as much shavings as when i first dropped the pan, and i can bet that hadnt been dropped in YEARS!
smell burnt????
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there is more than 1 way......
Former Vendor
Joined: Oct 2003
Posts: 90
Likes: 0
From: Houston Texas
I used a Jiffy lube to do the tranny fluid chg. on a Camaro a few yrs. ago.They hook up an inlet & outlet hose under the hood.They then fill up a portable hydraulic ram, with the new fluid. The piston pushes the new oil in, as the old fluid comes out. They also replaced the filter, in the tranny. They push the piston until they see new fluid coming out. This is the only way to ensure that the torque converter, and all metals are out of the car. Cost was about $60.00. Hope this helps
Le Mans Master
Joined: Sep 2003
Posts: 8,812
Likes: 2,029
From: eastern NC
On most RWD automatics, especially the earlier ones, there is a drain plug in the Torque Converter. Where by the way much of the fluid remains. Remove the inspection cover at the front of the transmission. You will immediately see the flex plate that the torque converter is bolted to.
The flex plate has numerous holes through it. Look carefully, and you should see one has a small pipe plug in it. You may have to rotate the engine (gently with a large screwdriver will work) to get to the plug. Then drain it normally.
Having said all that, some of the newer automatics are coming without plugs in their torque converters. But all of the early ones I've ever worked on have them.
GUSTO
The flex plate has numerous holes through it. Look carefully, and you should see one has a small pipe plug in it. You may have to rotate the engine (gently with a large screwdriver will work) to get to the plug. Then drain it normally.
Having said all that, some of the newer automatics are coming without plugs in their torque converters. But all of the early ones I've ever worked on have them.
GUSTO
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Originally Posted by GUSTO14
On most RWD automatics, especially the earlier ones, there is a drain plug in the Torque Converter.
The flex plate has numerous holes through it. Look carefully, and you should see one has a small pipe plug in it. Then drain it normally.
Having said all that, some of the newer automatics are coming without plugs in their torque converters. But all of the early ones I've ever worked on have them.
GUSTO
The flex plate has numerous holes through it. Look carefully, and you should see one has a small pipe plug in it. Then drain it normally.
Having said all that, some of the newer automatics are coming without plugs in their torque converters. But all of the early ones I've ever worked on have them.
GUSTO
Racer
Joined: Nov 2002
Posts: 359
Likes: 0
I'm not familier enough with the t350 to know which line is from the pump and which goes bac to the trans. You could find out by removing one line from the tranny and having someone start the car and shut it off while you see if the fluid shoots out of the tranny or out of the line. If it comes out of the line, that is the one you want. Just get a caseof trans fluid and pour fluid into the trans while letting the pump push it out of the line into a drain bucket. By the time you've used the whole case of fluid, it should be flushed out.
