Several Questions - The 1947 - Present Chevrolet & GMC Truck Message Board Network

raychevy · 01-20-2002, 04:31 PM

I own a 76 chevy made at the end of 76, so I guess its kinda a 77. The truck has 350 engine, with the automatic transmission. I believe the tranny is the Turbo 350, because the shift indicator has L1 and L2. When I bought the truck it had been sitting for several months. Sometimes it would not engage drive until I taped the gas, then it would without a problem. After driving it for a few weeks the engaging problem went away. I know the fluid in the tranny is light brown and nasty, but it still shifts fine. I want to change the fluid and filter to freshen it all up. I have heard people say that changing the fluid on the old trannies sometimes makes them fail. Has anyone seen that ? To change the filter dont I just remove the tranny pan, and put a new filter in there, and new gasket ? Then how much fluid do I pour back in ? I am looking at changing the entire cooling system this spring. Should I wait, and do all this at the same time ? I have never dont this, and need all the help I can get.
Thanks in advance
Ray

conoverbandit · 01-20-2002, 05:44 PM

Ok, I've been hoping I might could help a feller board member out sinc i joined this message board.So with that n mind I'll give it my best shot, I have heard the same thing as you have about pulling all the fluid, and putting all new in and in couple weeks, it won't go anymore.I have seen this happen several times.It is my understanding, that what happens is when you drain all the fluid,including the torque converter adn replace with all new, the new fluid "washes the varnish off the clutches" and so it quits pulling. This is what I do and it is my opinion, I'm sure several others have thier own as to how this works, but this is waht I do, I take pan off and let what's in the trans it's self drain, then I replace the filter and put the pan back on, and It should only take about 6 quarts of fluid to be back normal.I have a 78 Trans-am with a turbo 350 trans. and it done almost like what you were talking about, except mine evetually just got to slipping so bad she would'nt move.I asked everyone and whatever they told me to put in the fluid I did and it only got worse. So as a "last resort" I drained the tranny, and changed the filter, and put new gasket on . This tranny has over 120,000 onit when it went into this car, and after the filter change.It pulls better then it did in the other car. This is just my .02 worth, what I do , I hope it helps you out and sorry for being long winded.
Conoverbandit

raychevy · 01-20-2002, 08:06 PM

So you say to pull the pan, change filter, then start with 6 quarts of fluid, and see what happens ? THanks

gchemist · 01-21-2002, 08:28 AM

How many miles does the tranny have on it? If its over 100,000 then it will fail sooner or later. If you are really worried about changing the filer, I would just take it in and have the fluid flushed out. All the do is connect the lines and fill the tranny until nothing but new oil comes out the other end. This suggestion would depend on the tranny miles. The intial nonmovement was probably caused by your torque converter. If its working fine and the shifs feel good just change the filter and filler back up. A 350 has a square pan with one corner cut off.

------------------
Gerardo
1983 Custom Truck
TX Plates: "BAD BOW"
http://www.geocities.com/abetterchemist/

Longhorn Man · 01-21-2002, 09:52 AM

One thing I have found that works awsome in old trannys, is slick 50's tranny stuff. That stuff is magic.
Had a TH 350, car wouldn't move. Drained, added fresh fluid and filter, still wouldn't move, the kid was broke, I told him to get that stuff, the tranny lasted him 2 years an 45,000 miles before crapping out on him.
I know about 5 ppl who have same storys about it.
Now I happen to know there oil additive is crap, and won't put that stuff near an engine, but in an other wise junk tranny, I'll do it in a heart beat. Now I honestly put a bottle in at every fluid chainge as prevntitive maint, but only on old trannys. My new TH 350 won't see this stuff till it's old and ragged.
I am honestly still sceptical about it over real long times... I read and seen way too much bad stuff on there eng additives, that I wonder about this other stuff. But I have seen it work on old trannys on there last leg, and it helps.
Sorry so Long Winded this morning.

------------------
The hot rod;
a'69 G.M.C. Short/Fleet. 350 W/a heluva cam and nice stance. Trying to clean up the left over damage from the Dope-Smokin-Old-Man. See it at http://geocities.com/andys_69_gmc/

I've been dubbed the Longhorn Freak/Fanatic/Expert, I just hope I can live up to it. Check out my Longhorn site at http://geocities.com/MotorCity/Flats/8752/

Need to pick up the one ton Longhorn with a PONTIAC 350/350 here soon, thanks every one!

If you need a pic posted, e-mail me at longhornmail@yahoo.com
Columbus Ohio

raychevy · 01-21-2002, 07:23 PM

Lots of good info so far. The truck has 99 thousand miles on it. From what everyone is saying im going to change the filter and fluid for now. If it starts giving problems Ill use the slick 50 stuff and see how it works. The only reason for changing the fluid now, is because im sure its original fluid and filter. Thanks for all the good responses.

An882500 · 01-21-2002, 11:16 PM

Just remember that TH350's have a tendency to leak around the pan gasket alot. When you tighten the pan bolts remember to tighten them just past hand tight, until they are slightly snug. Cork gaskets have a tendency to fail more than the rubber or black paper ones. They are softer so just remember that. Oh and get the best pan gasket and filter you can. I skip the local parts houses and go to a tranny shop. They have the best ones. If you drain it and it has alot of metal shavings or "paper" pieces then your tranny is on it's way out. Don't forget to drain and clean the external tranny cooler if it has one. Alot of debris can be trapped in there and come back to haunt you. I hope this helps.

*Fast68Chevy* · 01-21-2002, 11:20 PM

weak pump, bad seals deteriorated due to heat and age, and worn down lcutch pack steels and plates, its old, its giving you the signs now, i wouldnt expect it to live for 25 more years lol.

The VIN will tell you year of truck, also look on door sticker for month and year code. Title also says year, you do have a title for that dont you ?
good luck!

------------------
A 68 C-10 panel and a 68 dually C-30 dump truck and a couple 71/72 chassis projects.
Randy- Lincoln, IL
r68c30@hotmail.com http://messenger.msn.com <A HREF="http://communities.msn.com/196772ChevroletCSTsforever
" TARGET=_blank>http://communities.msn.com/196772ChevroletCSTsforever
</A>

raychevy · 01-22-2002, 09:23 PM

The truck is flat weird on the year. The title is different, from the registration, and the insurance is 76 or 77. It says 76 on the door pillar,, I thinks its something like 11/76 so I guess its the 77 model. The trannys been doing good lately, and I take it easy on it now. Ill let yall know if it fails after I change the filter, gasket, and fluid.

01-20-2002, 04:31 PM	#1
raychevy Registered User Join Date: Jul 2000 Location: Evansville, Indiana USA Posts: 485	Several Questions I own a 76 chevy made at the end of 76, so I guess its kinda a 77. The truck has 350 engine, with the automatic transmission. I believe the tranny is the Turbo 350, because the shift indicator has L1 and L2. When I bought the truck it had been sitting for several months. Sometimes it would not engage drive until I taped the gas, then it would without a problem. After driving it for a few weeks the engaging problem went away. I know the fluid in the tranny is light brown and nasty, but it still shifts fine. I want to change the fluid and filter to freshen it all up. I have heard people say that changing the fluid on the old trannies sometimes makes them fail. Has anyone seen that ? To change the filter dont I just remove the tranny pan, and put a new filter in there, and new gasket ? Then how much fluid do I pour back in ? I am looking at changing the entire cooling system this spring. Should I wait, and do all this at the same time ? I have never dont this, and need all the help I can get. Thanks in advance Ray

01-20-2002, 05:44 PM	#2
conoverbandit Registered User Join Date: Dec 2001 Location: Conover,N.C.USA Posts: 217	Ok, I've been hoping I might could help a feller board member out sinc i joined this message board.So with that n mind I'll give it my best shot, I have heard the same thing as you have about pulling all the fluid, and putting all new in and in couple weeks, it won't go anymore.I have seen this happen several times.It is my understanding, that what happens is when you drain all the fluid,including the torque converter adn replace with all new, the new fluid "washes the varnish off the clutches" and so it quits pulling. This is what I do and it is my opinion, I'm sure several others have thier own as to how this works, but this is waht I do, I take pan off and let what's in the trans it's self drain, then I replace the filter and put the pan back on, and It should only take about 6 quarts of fluid to be back normal.I have a 78 Trans-am with a turbo 350 trans. and it done almost like what you were talking about, except mine evetually just got to slipping so bad she would'nt move.I asked everyone and whatever they told me to put in the fluid I did and it only got worse. So as a "last resort" I drained the tranny, and changed the filter, and put new gasket on . This tranny has over 120,000 onit when it went into this car, and after the filter change.It pulls better then it did in the other car. This is just my .02 worth, what I do , I hope it helps you out and sorry for being long winded. Conoverbandit __________________ 71 GMC 3/4 ton converted to dually 75 chevy swb 4x4 78 pontiac trans-am----sold, so long old friend..... 87 Crew Cab 2x 454 93 chevy hi top conversion

01-21-2002, 08:28 AM	#4
gchemist BAD BOW-Silverado XST Join Date: May 2000 Location: Senior Member from Austin, TX Posts: 6,431	How many miles does the tranny have on it? If its over 100,000 then it will fail sooner or later. If you are really worried about changing the filer, I would just take it in and have the fluid flushed out. All the do is connect the lines and fill the tranny until nothing but new oil comes out the other end. This suggestion would depend on the tranny miles. The intial nonmovement was probably caused by your torque converter. If its working fine and the shifs feel good just change the filter and filler back up. A 350 has a square pan with one corner cut off. ------------------ Gerardo 1983 Custom Truck TX Plates: "BAD BOW" http://www.geocities.com/abetterchemist/ __________________ Gerardo a.k.a. Mad Chemist Silverado XST videos

01-20-2002, 08:06 PM	#3
raychevy Registered User Join Date: Jul 2000 Location: Evansville, Indiana USA Posts: 485	So you say to pull the pan, change filter, then start with 6 quarts of fluid, and see what happens ? THanks

01-21-2002, 09:52 AM	#5
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	One thing I have found that works awsome in old trannys, is slick 50's tranny stuff. That stuff is magic. Had a TH 350, car wouldn't move. Drained, added fresh fluid and filter, still wouldn't move, the kid was broke, I told him to get that stuff, the tranny lasted him 2 years an 45,000 miles before crapping out on him. I know about 5 ppl who have same storys about it. Now I happen to know there oil additive is crap, and won't put that stuff near an engine, but in an other wise junk tranny, I'll do it in a heart beat. Now I honestly put a bottle in at every fluid chainge as prevntitive maint, but only on old trannys. My new TH 350 won't see this stuff till it's old and ragged. I am honestly still sceptical about it over real long times... I read and seen way too much bad stuff on there eng additives, that I wonder about this other stuff. But I have seen it work on old trannys on there last leg, and it helps. Sorry so Long Winded this morning. ------------------ The hot rod; a'69 G.M.C. Short/Fleet. 350 W/a heluva cam and nice stance. Trying to clean up the left over damage from the Dope-Smokin-Old-Man. See it at http://geocities.com/andys_69_gmc/ I've been dubbed the Longhorn Freak/Fanatic/Expert, I just hope I can live up to it. Check out my Longhorn site at http://geocities.com/MotorCity/Flats/8752/ Need to pick up the one ton Longhorn with a PONTIAC 350/350 here soon, thanks every one! If you need a pic posted, e-mail me at longhornmail@yahoo.com Columbus Ohio

01-21-2002, 07:23 PM	#6
raychevy Registered User Join Date: Jul 2000 Location: Evansville, Indiana USA Posts: 485	Lots of good info so far. The truck has 99 thousand miles on it. From what everyone is saying im going to change the filter and fluid for now. If it starts giving problems Ill use the slick 50 stuff and see how it works. The only reason for changing the fluid now, is because im sure its original fluid and filter. Thanks for all the good responses.

01-21-2002, 11:16 PM	#7
An882500 Registered User Join Date: Sep 2001 Location: Corona, CA, US Posts: 29	Just remember that TH350's have a tendency to leak around the pan gasket alot. When you tighten the pan bolts remember to tighten them just past hand tight, until they are slightly snug. Cork gaskets have a tendency to fail more than the rubber or black paper ones. They are softer so just remember that. Oh and get the best pan gasket and filter you can. I skip the local parts houses and go to a tranny shop. They have the best ones. If you drain it and it has alot of metal shavings or "paper" pieces then your tranny is on it's way out. Don't forget to drain and clean the external tranny cooler if it has one. Alot of debris can be trapped in there and come back to haunt you. I hope this helps.

01-21-2002, 11:20 PM	#8
Fast68Chevy Account Suspended Join Date: May 2000 Location: IL Posts: 0	weak pump, bad seals deteriorated due to heat and age, and worn down lcutch pack steels and plates, its old, its giving you the signs now, i wouldnt expect it to live for 25 more years lol. The VIN will tell you year of truck, also look on door sticker for month and year code. Title also says year, you do have a title for that dont you ? good luck! ------------------ A 68 C-10 panel and a 68 dually C-30 dump truck and a couple 71/72 chassis projects. Randy- Lincoln, IL r68c30@hotmail.com http://messenger.msn.com <A HREF="http://communities.msn.com/196772ChevroletCSTsforever " TARGET=_blank>http://communities.msn.com/196772ChevroletCSTsforever </A>

01-22-2002, 09:23 PM	#9
raychevy Registered User Join Date: Jul 2000 Location: Evansville, Indiana USA Posts: 485	The truck is flat weird on the year. The title is different, from the registration, and the insurance is 76 or 77. It says 76 on the door pillar,, I thinks its something like 11/76 so I guess its the 77 model. The trannys been doing good lately, and I take it easy on it now. Ill let yall know if it fails after I change the filter, gasket, and fluid.



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