1998 Buick Park AvenueTransaxle fluid and filter change

[Spriteman]

Decided to do my trans fluid and filter this weekend. Here's a link to a few pics - https://plus.google.com/photos/1181...s/6108064692490459217?authkey=CIz30YzTs_HOugE


I started by removing as much fluid as I could through the filler tube via HF hand pump - filled up a gallon oil jug to the top - so I'm guessing that was right at 5 quarts. Then I loosened and removed the front and side bolts on the trans pan following the FSM instructions - then tapped the pan bottom with a rubber mallet. Loosened the back bolts and allowed the pan to drop an inch or so in the front allowing the rest of the fluid to drain out. Removed the back bolts and lowered the pan cover.

With 105K miles on the 1998 BPA I don't think the fluid or filter was ever changed. It was dark dark red but did not smell burnt and I had no trans issues I just wanted to get ahead of any problems.

There was a small amount of grey silt on the top side of the filter but there was no sign of metallic material - also there was no metallics on the magnet - I'm thinking that's a good thing.

During refill I put back in right at 7 quarts which is what the FSM says a filter change should take.

My only problem was when I was remounting the cover - I had all 20 bolts attached to finger tight and started tightening with torque wrench to 12 ft/lbs per the FSM. I was using my new torque wrench and the bolts just kept tightening and I knew that I was going past 12 ft/lbs. Finally, I broke off one of the bolts in the trans case - luckily there are enough bolts to allow for a good seal without one.

After that I just tightened up the rest of the bolts to what I felt would be a good torque by hand and left it at that. Anyone have any suggestions for removing the broken bolt and ordering a new one. The thread hole goes all of the way through the case - I can feel the other end of the bolt above.

Other than that the change went well - hope the pics are informative and helpful.

 

[HotZ28]

Sounds like you have many miles left on the trans, especially after changing the fluid/filter. I hope you used Dexron VI, or Valvoline Maxi-Life fluid! The broken bolt will have to be drilled and use an ease-out to remove. That could be very difficult with the pan in place! Anyway, I would not worry about it unless you develop a leak in that area.

 

[Spriteman]

Hey HotZ - thanks for the response. How many miles would you say I should wait before I do my 2nd and 3rd fluid changes on my way to changing all of the fluid out?

Used Max Life as recommended.

On the next change I may drop the pan again and drill it out - do you think it's possible to not have to re-tap the threads if I can stay away from the existing threads?

 

[HotZ28]

IIRC, the pan bolts are M6 X 1.0 X 17 which is about the same size as an SAE 1/4" bolt. If the bolt was a clean break (flush with the trans flange) you might be able to use a center punch to locate and ding the center of the stud. You will not have much room for error. BTW, what size torque wrench were you using 1/4", 3/8" or 1/2". Of course, the smaller the better for small bolts. I know what the FSM says, but I would never torque an M6 bolt more than 10 ft lbs.

I would drive about 5K, then evacuate 4-5 qts out through the dip-stick tube, rather than dropping the pan. Then do the same procedure again after another 5K and you should be good for another 100K.

 

[Cadillac_AL]

Since those bolts almost never get frozen in place, it should be much easier than an exhaust manifold bolt or something. You may get lucky by just using a reverse drill bit to drill it out. If that doesn't spin it out then an easy out should take it out easily. You shouldn't have to resort to retapping it. I would throw that torque wrench in the trash unless it's a 1/2" drive. 1/2" drive isn't good for low torque readings anyway.

 

[LMG1438]

I changed my fluid and filter i put in 7 Qts ,wish i used a better filter like AC Delco 1998 PA Base

 

[LMG1438]

Also i was going to do a flush at first rather than just pan fluid and filter, i called serveral shops one guy said if the trans wasn't flushed at regular intervals as reqiured in the owners manual that it would do more harm than good.

Any thoughts on this?

 

[Spriteman]

It is indeed a 1/2 wrench - I was thinking about borrowing a "in lbs" wrench to hit that lower torque value.

Should have gone with my gut - luckily it's the bolt right on the front corner - easier to access.

I can make out an 88 on the bolt - I'm pretty sure it's an 8mm - could be wrong.

 

[HotZ28]

The 8.8 does not indicate the size of the bolt, but the class of the bolt, which is Medium Carbon Steel, Quenched and Tempered.

In addition, the hex on an 6mm would require a 10mm socket. If it were an 8mm bolt, it would require an 13mm socket. Do you recall the size of the socket you used? Are you sure the FSM torque specs called for 12 ft lbs, or could it have been N/m? If you convert 12 n/m to ft lbs, that would be 8.850745788 ft lbs. Metric bolt torques are specified in Newton Meter (N/M). See bolt size and torque specs in the last link below.

https://www.boltdepot.com/fastener-information/Materials-and-Grades/Bolt-Grade-Chart.aspx
https://www.boltdepot.com/fastener-information/Bolts/Metric-Bolt-Head-Size.aspx
https://www.boltdepot.com/fastener-information/Bolts/Metric-Recommended-Torque.aspx

 

[The Avenue]

I had done the same thing to 2 pan bolts. The reverse drill bit I had was junk and broke. Dad had a Stanley set and it got in there and saved the day. I went to the local Ace with a pan bolt and they had a match. Theirs are a thread or 2 shorter but tightened with no problems!

 

[FFarr]

If the hole goes all the way through and the bolt isn't cross-threaded or locked in the hole, you may be able to drill the bolt and spin it out the top. Drill exactly the center of the broken bolt with something like a 3/32" or 1/8" drill. When the drill starts to break through the end of the bolt, the drill will grab and hopefully the broken piece will spin out the top.
If not, you have a hole for an eze-out. Go slow, drilling the center of the bolt is the key.

 

[Spriteman]

Verified that the bolt head requires a 10mm socket so that matches with the 6mm bolt mentioned before.

Also picked up a 1/4 in "in lbs" torque wrench today - will use that when I drop the pan to get the broken bolt out.

I appreciate all of the helpful comments - I'm going to try and give the broken bolt a punch in the center then try drilling it out through the top. If that doesn't grab I'm going to make sure I have a good ez-out handy.