86 auto transmission filter replacement
Thread Starter
Instructor
Joined: Sep 2018
Posts: 212
Likes: 37
From: Southeast Virginia
86 auto transmission filter replacement
While I have the pan off is there anything else I should do other than just looking at fluid, magnet, etc?
It had some strange shifts after getting warm yesterday and today. Fluid hasnt been changed in 5 years of sitting so I figured I should go ahead and take care of the filter and fluid and see if that helps.
It had some strange shifts after getting warm yesterday and today. Fluid hasnt been changed in 5 years of sitting so I figured I should go ahead and take care of the filter and fluid and see if that helps.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
Make sure you have correct gasket. Many times bolt holes are "dimpled" towards gasket. With a small ball peen hammer and regular hammer ; light ly tap and reverse distortions at bolt holes. It will help prevent leaks afterwards.
Melting Slicks
Joined: May 2013
Posts: 2,692
Likes: 349
From: Sacramento California
^ in other words, you want the bolt holes on the pan to be pointed (cone shaped) slightly toward the bolt heads and away from the transmission gasket.
When the bolts are tightened, they tend to push the bolt holes in toward the gasket and this needs to be reversed for a good seal during your service work.
After removing the pan, you might want to check if any of the exposed fasteners are loose, like on the valve body, etc. I would not fully torque them after so much time and heat cycles some of the plastic crap might crack. Just be sure none of them are loose.
When the bolts are tightened, they tend to push the bolt holes in toward the gasket and this needs to be reversed for a good seal during your service work.
After removing the pan, you might want to check if any of the exposed fasteners are loose, like on the valve body, etc. I would not fully torque them after so much time and heat cycles some of the plastic crap might crack. Just be sure none of them are loose.
Last edited by DGXR; Mar 10, 2020 at 02:15 PM.
Thread Starter
Instructor
Joined: Sep 2018
Posts: 212
Likes: 37
From: Southeast Virginia
Thanks! That makes a lot of sense about the bolt holes. I'll make sure to check them so they are fixed for the reinstall of the pan. I have done several of these before and didn't think to do that in the past. That's a great tip. I even worked at Jiffy Lube for several years while in college. I'll def check the valve body too. Thanks again!
Thread Starter
Instructor
Joined: Sep 2018
Posts: 212
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From: Southeast Virginia
Well, I went to do the filter and gasket last night and one bolt did not want to come out. It was right in the rear corner on the passenger side. Some of them seemed like they had corrosion on the threads (not cross threaded) from sitting for 5 years under a tree I guess. Well, anyway, the bolt broke off in the transmission. I know I can drill it out, tap it and put another one in there BUT my question is...do you think that due to the location I would be ok with just torquing all the other bolts to spec and it not leak? There are two other bolts very close to that one that is in the corner.
Melting Slicks
Joined: May 2013
Posts: 2,692
Likes: 349
From: Sacramento California
I strongly suggest fixing it properly while everything is up in the air and accessible. It should be relatively quick and easy fix. If you take a shortcut, it might not leak right now but it could leak later, and this possibility may stick in your mind as long as you own this car. By fixing it right, you will have peace of mind driving the car, and you will have confidence and experience from doing the right thing. Don't shortcut this one.
EDIT: next time a stuck bolt happens, try tightening it slightly, just to break it loose. Back and forth tightening/loosening very slightly until the corrosion breaks. Penetrating oil and heat are very helpful, just don't catch yourself on fire using both at the same time.
EDIT: next time a stuck bolt happens, try tightening it slightly, just to break it loose. Back and forth tightening/loosening very slightly until the corrosion breaks. Penetrating oil and heat are very helpful, just don't catch yourself on fire using both at the same time.
Last edited by DGXR; Mar 11, 2020 at 01:01 PM.
Thread Starter
Instructor
Joined: Sep 2018
Posts: 212
Likes: 37
From: Southeast Virginia
I did try going back and forth with it and thought it was good to go. Plus I lost a little patience with transmission fluid all over me. I rushed it and now am paying for it...literally. You are so right, I need to go ahead and fix it. It will bother me if I don't. So I guess drill it out, tap it and put a new bolt in it is then.
Last edited by c B; Mar 11, 2020 at 01:18 PM.
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Intermediate
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Thread Starter
Instructor
Joined: Sep 2018
Posts: 212
Likes: 37
From: Southeast Virginia
Just a small tip for next time. Pick yourself up a fluid suction pump and a long extension tube. Whenever I change the transmission fluid on a vehicle, I suck out as much as possible through the dipstick tube using a suction pump. On the Corvette, I can almost drain the pan dry. When I drop the pan to change the filter, there is no mess at all.
Burning Brakes
Joined: Jan 2015
Posts: 875
Likes: 76
Just a small tip for next time. Pick yourself up a fluid suction pump and a long extension tube. Whenever I change the transmission fluid on a vehicle, I suck out as much as possible through the dipstick tube using a suction pump. On the Corvette, I can almost drain the pan dry. When I drop the pan to change the filter, there is no mess at all.
Something I've done when I've changed my break fluid. Is I have a large pickle jar with some attachments in the lid for two tubes to connect. And one tube would go on the brake bleeder screw. And the other tube would go to a Might-Vac. And I'd pull a vacuum in the pickle jar to suck break fluid into the pickle jar.
Intermediate
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West Marine oil extractor
Burning Brakes
Joined: Jan 2015
Posts: 875
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Here is a link to a kit that West Marine sells. There are several similar kits out there, but this is the one that I have. It came with 3 different size suction tubes.
West Marine oil extractor
West Marine oil extractor
Did you stick with Dexron 3 or did you go to 6? I've always stuck with 3, but may go with 6 on refill.
Intermediate
Joined: Jun 2018
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I stick with a good quality name brand dex 3. The suction pump makes a fluid change quick and easy, and the Dex 3 is cheap enough, so I change the trans fluid every time I change the oil. The trans filter gets changed every 20k.
Thread Starter
Instructor
Joined: Sep 2018
Posts: 212
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From: Southeast Virginia
I have not proven it yet but I think Dex VI is causing my shifting problems. I agree with 28uniflite in sticking with Dex III. I will be replacing my fluid with Dex III and sticking with that from now on.
However it may be an issue that it is mixed in my trans. I don't have the money to try it but I'm wondering if I changed to ALL Dex VI if that would clear things up. But for now I'm just going with Dex III from now on.
However it may be an issue that it is mixed in my trans. I don't have the money to try it but I'm wondering if I changed to ALL Dex VI if that would clear things up. But for now I'm just going with Dex III from now on.
Last edited by c B; Apr 14, 2020 at 09:35 AM.