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1997 Pontiac Firebird WS6, 5.7L V8, LT1 348
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Discussion Starter · #1 · (Edited by Moderator)
Greetings Firebird Nation,

As many of you know I inherited a Firebird late last year and have been working to restore it ever since. Since the weather has been improving I recently jacked it up to start working on the water pump and Opti-Spark. However, after inspecting the underside of the car it has become obvious that the transmission is leaking fluid. This makes since because the car had to be driven about two hours to get it home. When we got it home it would not go in reverse the next day. I checked and notice there was no fluid on the stick and immediately added fluid which resolved the problem.

I hoped that maybe someone recently did a fluid change or something and just failed to keep checking the stick. That was wishful thinking as now it looks like it is leaking pretty good all around the pan. I am fairly certain when I researched the car I found that it had the 4L60E in it. I am getting ahead of myself because I am literally right in the middle of a large project right now with the water pump and Opti but I am hoping to get some information on this as soon as possible. Specifically, I have never experienced a leaking transmission before and have no clue where to start. Also the car has 140,000 miles on it.

1.) I realize it is probably impossible to troubleshoot from here but what are my chances that this is something simple like the gasket around the pan being rotted/faulty? Basically can anyone tell me if I have a better chance of something simple versus something catastrophic?

2.) How can I even begin to troubleshoot something like this anyway? Like is there a way to pressurize the system and check for leaks? The only thing I can think of is to start it after I got my current project done and leave it on the jack stands and see if I can see any obvious culprits. Maybe even a little soap and water?

I cannot even complete one project before locating something else on this car that needs work. I realize it is nearly twenty-five years old but damn, I hope to catch a break soon. I have been leaning towards selling it more and more. I am just not capable of not being honest upfront with whoever is interested in it and knowing these things I do not know is going to give me any kind of money for it.
 

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If I remember correctly, your car has sat for a while before you obtained it. This can cause all sorts of leak problems because gaskets & seals dry out and now leak.

You might be lucky enough and change the trans fluid pan gasket and solve your problem. But, you could have a warped pan. This is because ham fisted mecanics over tighten the pan bolts causing this. When changing the pan gasket, have an torque wrench to do final tighten down of bolts. Get 96 service manual at following link. It wiil have proper torque listed and proper tightening sequence of bolts. http://www.mediafire.com/?40mfgeoe4ctti

There are other places where trans can leak. The rear seal of trans is one of these. To chnge it, the drive shaft and rear extension housing must be removed.

Another common leak point is the rear seal of engine. And front seal of trans. Both of these require removal of trans to change. The engine rear seal would also require you to remove flex plate. And when removing the flex plate, mark the flex plates relation to the engine. And don't rotate engine after removing plate. Also mark which side of plate goes towards trans and which side goes towards engine. It makes a difference.

I know someone who installed the flex plate backwards. It cause engine to turn a little way and then lock up. Don't make the same mistake he did.

Any place a component or control shaft or cable goes into trans, these are potential leak points. And because your car sat, the vent tube at top of trans bellhousing area can have insects crawl in, build their nests of dirt. This will clog the vent tube and cause fluid to come out where dipstick tube goes in trans.

The manual will have complete 4l60E service & rebuild info.
 

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1997 Pontiac Firebird WS6, 5.7L V8, LT1 348
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Discussion Starter · #3 · (Edited by Moderator)
If I remember correctly, your car has sat for a while before you obtained it. This can cause all sorts of leak problems because gaskets & seals dry out and now leak.

You might be lucky enough and change the trans fluid pan gasket and solve your problem. But, you could have a warped pan. This is because ham fisted mecanics over tighten the pan bolts causing this. When changing the pan gasket, have an torque wrench to do final tighten down of bolts. Get 96 service manual at following link. It wiil have proper torque listed and proper tightening sequence of bolts. http://www.mediafire.com/?40mfgeoe4ctti

There are other places where trans can leak. The rear seal of trans is one of these. To chnge it, the drive shaft and rear extension housing must be removed.

Another common leak point is the rear seal of engine. And front seal of trans. Both of these require removal of trans to change. The engine rear seal would also require you to remove flex plate. And when removing the flex plate, mark the flex plates relation to the engine. And don't rotate engine after removing plate. Also mark which side of plate goes towards trans and which side goes towards engine. It makes a difference.

I know someone who installed the flex plate backwards. It cause engine to turn a little way and then lock up. Don't make the same mistake he did.

Any place a component or control shaft or cable goes into trans, these are potential leak points. And because your car sat, the vent tube at top of trans bellhousing area can have insects crawl in, build their nests of dirt. This will clog the vent tube and cause fluid to come out where dipstick tube goes in trans.

The manual will have complete 4l60E service & rebuild info.
Yes, it did sit for some time. I have no way of knowing how long and how many times it was driven in between. My mother told me that the original owner of the car did take it out from time to time to make certain it was not just sitting. However, after he started to get sick he may have stopped doing that so much and it may have sit even more.

EDIT:

Also what are my chances of finishing up my current project, then starting the car and inspecting it for leaks? Could it make a pan leak or any other leak more obvious to spot?
 

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Discussion Starter · #4 ·
Okay so came home from work dirty today so decided to go ahead and take off the transmission pan before it got dark. It was very pleasant to see this is nothing like my 2007 Silverado. The shift linkage is attached to the pan via a bracket which is so nice. As in after the two bolts were removed it just pulls away. So I noticed that one of the bolts (I believe the one that is toward the back of the car in the bracket) is about double the length of the other bolts. However, the other one for this bracket seems to be a standard transmission bolt. Is this correct?

As you may be able to see I was also able to get the pan filter out as well. I will probably make a trip to the auto parts store tomorrow to get a replacement. Does anyone know if the little plastic ring/gasket that goes between the neck of the filter needs to be replaced? I did it in my truck and it was not pleasant. I have an idea of how to get it out now but still. I have this Lube Locker gasket that I think I am still going to use regardless. I think it will do a better job. It was immediately apparent that the gasket was the problem. As soon as I took out some of the bolts fluid started dripping from them. I guess this is pretty good news.

I also usually flush the system but with all the new fluid that has been added I hope that it is clean enough. The stuff in the bottom of the pan definitely leads me to believe it has never been changed, that and the smell.

So I guess my biggest inquiry would be should I attempt to torque these bolts down to specifications or just get them tight and call it? Because when I did this on my truck I used a torque wrench (a very old crappy one I should not have been using) and broke one bolt. My father managed to get it out while I was at work one day and he said it did not seem that tight. The only two bolts I have ever broken using a torque wrench is that one and another in soft metal/aluminum housing that seems to fail to stop the torque wrench. Anyway as always any advice would be greatly appreciated. I plan to just clean the surfaces and pan up as best as I can then hope that is good enough.

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you should use a CALIBRATED torque wrench. Look to youtube or the web for instructions on how to calibrate one. it's not hard, but the length of the handle plays into it so I can't just tell you what worked for me. It won't translate.

I would recommend the torque wrench. All the "tins" on a vehicle such as oil pan, valve covers, transmission pan, and differential covers develop leaks if overnighted more than a couple inch-pounds. The bolt hole deforms and they need replaced or "flattened". Valve covers I'd risk as there isn't going to be much if any fluid loss because not enough volume of fluid pumps through them to be a significant source of oil leaking.

Everything else though, you only want to pay to fill once. I mean, you could recycle the fresh fluid but I wouldn't recommend it and don't know anyone who would.
 
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Discussion Starter · #6 ·
you should use a CALIBRATED torque wrench. Look to youtube or the web for instructions on how to calibrate one. it's not hard, but the length of the handle plays into it so I can't just tell you what worked for me. It won't translate.

I would recommend the torque wrench. All the "tins" on a vehicle such as oil pan, valve covers, transmission pan, and differential covers develop leaks if overnighted more than a couple inch-pounds. The bolt hole deforms and they need replaced or "flattened". Valve covers I'd risk as there isn't going to be much if any fluid loss because not enough volume of fluid pumps through them to be a significant source of oil leaking.

Everything else though, you only want to pay to fill once. I mean, you could recycle the fresh fluid but I wouldn't recommend it and don't know anyone who would.
So I just bought some nice ICON torque wrenches from Harbor Freight, they get good reviews. I also bought a 'torque adapter reader' contraption that basically goes between the torque wrench and the socket and tested them out. It seems to be pretty accurate because I tried to test it thoroughly and the wrenches clicked pretty consistently right at what I had it set to. I have been using them for anything that I think may be critical like the water pump bolts for example. So I will give it a go with these transmission bolts. I am confident these torque wrenches will get the bolts close to whatever I set them to.

I just read that the torque specification for the 4L60e is 9 FT LBS and my smaller wrench only goes down to 20. I will have to figure something out or borrow one and test it first.

EDIT:
When I took them off they were noticeably loose. I realize that they are not suppose to be very tight but they did not give hardly any resistance when starting to remove them. I want to say I remember them being much tighter on my Silverado and I am almost certain the pan had never been removed from my old truck.
 

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1994 Firebird Formula 381ci LT1 / TH400+GV O/D
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You should have a “lb-inch” torque wrench. There are numerous bolts on the car that are torqued to lb-inch specs. When I read your comment about breaking the truck pan bolts, my first thought was “wrong torque wrench”.

Just an example:

 
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You should have a “lb-inch” torque wrench. There are numerous bolts on the car that are torqued to lb-inch specs. When I read your comment about breaking the truck pan bolts, my first thought was “wrong torque wrench”.

Just an example:


Exactly what he said. Small torque wrenches are usually stamped in inch-pounds, so pay attention to the stamping. What you see as "20" could very well be 20 inch-pounds which is actually just shy of 2 foot-pounds. Same math as we learned in school. 12 inches to a foot, 12 inch-pounds to a foot pound. So, if you saw 144 inch-pounds, you could use either wrench. The inch-pound wrench gets set to 144, and the foot-pound wrench gets set to 12.

I too immediately thought "wrong torque wrench".
 
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Discussion Starter · #9 ·
You should have a “lb-inch” torque wrench. There are numerous bolts on the car that are torqued to lb-inch specs. When I read your comment about breaking the truck pan bolts, my first thought was “wrong torque wrench”.

Just an example:

Yes, both of mine start off at 20 FT LBS. I had a lot on my mind when I went to purchase the second one and I think I meant to purchase the 40-200 IN LBS one and at the time I may have mistook it for FT LBS. I remember looking at the smaller one and thinking it was strange. Oh well I do not think I want to spend another hundred bucks right now either. So today I got the little neck ring/gasket thing out and replaced the filter. Hopefully tomorrow I can get the pan back on then make my decision.

The bolts were absolutely covered in sludge. I wiped them off as best as I could one by one and now they are soaking in fresh transmission fluid. Can someone tell me if it is okay to just pull them out of this cup and put them in to secure the pan or should I wipe them off again?

This Lube Locker gasket looks like it is going to work well and hope it does. Also is it okay to clean the pan and magnet up with brake cleaner? It is how I have always done it but I know some people are against it.

Lastly, the truck I was referring to was several years ago and it was my first time dropping a pan. That job was all bad. You have to either pry over the shift linkage or remove part of the muffler to get the pan to come down. Anyway I was rushing to get the job done like now and the only torque wrench I had was the manual one with the needle on it. It is possible I was still looking at the wrong setting that time around. It looked exactly like this:


I think from now on I am only going to post thumbnails so the pictures do not take up so much room on my threads.

Wood Rectangle Gas Auto part Composite material
 

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Sort of off topic, I apologize.

I have a beam-style torque wrench like the one you linked above. It's a Craftsman, from back in the day when Craftsman was a good quality, made in USA, guaranteed for life brand (unlike today's K-Mart versions). I gave it to my father as a gift 60+ years ago. I got it back, along with a large number of 60+ year old Craftsman tools, when he passed away.

From time to time I‘ll grab the beam wrench when I'm too lazy to dig a clicker from its protective case. Also inherited a vintage Snap-On Torq-O-Meter dial torque wrench. Gotta be a hundred years old.
 
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