Trans pan bolts...

[The Yeti]

Just curious and haven't seen this mentioned in any searches. In a ZF 8 Speed (well, more specifically the ZF 8 speed in a BMW X5 which has a 'plastic' pan) They tell you to replace the pan bolts when changing the transmission fluid as they are "torque to spec" or like a stretch bolt, those little torx deals. So my questions is, can you reuse the tranmission pan bolts when dropping the pan, changing out the 7 ish liters you might get out (if changing cold) and swapping out, what I understand is a repalceable filter and reinstalling the pan before refilling on the Gladiator?
I've found apparently the pan gasket is reusable, pan is steel with a filter that can be removed and replaced but no mention of the bolts when doing the process on the JT.
Wasn't sure where to post this either, maintanance or transmission but here it is 50/50 chance

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[kevman65]

The "kits" that are available have the filter, gasket, O-ring, and fluid.
No bolts.

With that said, refer to the owners manual to verify.

Just checked something and it may be that the PPE pan is thicker and requires a longer bolt, but the PPE comes with new bolts and washers.

 

[whysoserious]

BMW likes aluminum bolts in various applications, which are one time use once they are torqued to their appropriate stretch. I'm guessing the X5 uses said bolts for the trans pan.

 

[The Yeti]

Thanks for the replies. I'm going to assume if the 'Mopar' kits don't come with bolts then they would be reusable.
If it's an issue of aluminum bolts not being reusable then I guess the next question, to get technical, would be are the Jeep bolts not aluminum then? I mean honeslty, I'll probly just reuse the bolts knowing they don't normally come with the standard parts you would order for the task but curious now.

 

[Maximus Gladius]

Grab a magnet and see if the pan bolts are magnetic or not.

 

[The Yeti]

Good call. Didn't even think of that. It's been a long day haa.

 

[Maximus Gladius]

The transmission pan bolts on my 21 JTR are metal.

 

[ShadowsPapa]

The transmission pan bolts on my 21 JTR are metal.

Ferrous metal.


They are steel bolts. Same as our 4xe has. (I dealt with a leaking transmission a year or so ago)

89 in/lbs, steel bolts, no mention of "one time use" and they are not torque plus angle. I doubt these are torque-to-yield as that would be a strange place to use such a fastener, and the FCA torque specs don't mention anything about "do not re-use".

I'd use the again. (I'd also do a recheck on them after some heating and cooling, a couple of drives or so)

 

[The Yeti]

Well that solves my wandering mind until the morning when I might've worked up the ambition to go check. Right before thinking, 'is the magnet sticking to the pan or the bolt...?' Lol

Yup makes sense to me. Most of the BMW stuff seemed to lean toward a money grab and was in design made to make most rather go to the dealer than attempt anything themselves. They didnt make much service info easily available to the DYI guy, but you could figure it out with a little effort. Which gets a guy who wants to figure it out look in to the manufacturer of the part leading to learning more than the dealer of the vehicle would lead a person to believe vs what the manufacuter would advise.

When I get to it I'll just torque to spec in whatever pattern (can't remember ill have to look it up) and call it a night. Thanks all for helping me satisfy my curiousity here. Some good info either way.

 

[Maximus Gladius]

My service manager printed off the instruction sheet for pan removal and I had asked him about the “one time use” bolts. He said the sheet says to use “new” bolts but they often reuse the same ones with no issue. As ShadowsPapa said, they’re ferrous metal -steel. (Thanks Bill)

Honestly, 89 in lbs doesn’t feel like much on the small in torque bar. The rubber gasket doesn’t require much force at all to seal correctly. Follow the sequence pattern. My unprofessional, unlearned way of torquing these down is to first set the torque to the 50% of 89 in lbs and go around in sequence, then set it tighter to 75% and do it again, then go around for the last time at 89 in lbs. Never had any seepage doing that.

This is the way, (for me) and let’s be clear, if I’ve done it all wrong, it worked for me. The most important part of dropping your pan (DIY style) is in making sure your transmission surroundings are clean. I’m anal and I don’t want dust blowing around, I don’t want to be pulling the pan off with the outside of the transmission oily or dirty so I pressure wash all around the outside of the pan and sides of the transmission and get the dirt off. I then spray brake cleaner around that pan lip and use a copper brush and quickly go around the lip on the pan and transmission body, then the night before I drop the pan I sweep and hose off the floor and wash all the dirt out and in the morning the floor is clean and dry.

Again, this is just what I do.

 

[ShadowsPapa]

Honestly, 89 in lbs doesn’t feel like much on the small in torque bar. The rubber gasket doesn’t require much force at all to seal correctly. Follow the sequence pattern. My unprofessional, unlearned way of torquing these down is to first set the torque to the 50% of 89 in lbs and go around in sequence, then set it tighter to 75% and do it again, then go around for the last time at 89 in lbs. Never had any seepage doing that.

This is the way, (for me) and let’s be clear, if I’ve done it all wrong, it worked for me. The most important part of dropping your pan (DIY style) is in making sure your transmission surroundings are clean. I’m anal and I don’t want dust blowing around, I don’t want to be pulling the pan off with the outside of the transmission oily or dirty so I pressure wash all around the outside of the pan and sides of the transmission and get the dirt off. I then spray brake cleaner around that pan lip and use a copper brush and quickly go around the lip on the pan and transmission body, then the night before I drop the pan I sweep and hose off the floor and wash all the dirt out and in the morning the floor is clean and dry.

Exactly a great way to do pan bolts - be it a SBC 350 oil pan or a transmission pan on a TF998 or these. Half, 3/4, then full. You can't go wrong.

Cleanliness is God in automatic transmissions. As we were taught in class (an entire semester on transmissions and differentials) the clearance between the shuttles/valves in the valve body and the bore wall is a fraction of the diameter of a human hair. A piece of lint from a cotton rag can cause the valve to lock solid. (sadly, I've seen it happen, causing a band servo to bust off the case, literally)
My boss gifted me a custom built work table for automatics - nice slick, smooth steel surface with drain troughs on either side that led to a bucket below and boxes of lint-free rags to use. I pressure washed and brushed off the transmissions before they hit the bench, and I could squeegee the fluid and other stuff to the troughs, and empty the bucket when done. The table stayed clean. Parts were washed up and covered until reassembly because of course it was a shop just off an alley, lots of dust and such in the air.

Some people get lucky working on them in the dirt, but it only takes one time and you have a mess on your hands and a very expensive problem, due to a piece of LINT or hair or dirt that got into the wrong place.

100% on torquing low bolts on pans, heck, even head to block bolts for that matter. Follow the pattern, break it down into at least 2, even 3 stages of "tightening".

I just HAD to pick on the "metal bolt" bit as a person who also deals with chemistry, over 90 of the elements on the periodic table are metals - sodium, calcium, aluminum, indium - in other words, you could have held up a bolt made of sodium (EXTREMELY CAREFULLY) and said it was made of metal.. LOL - yeah, just had to do that! Sorry.

NOTE - those instructions don't mention discarding the pan bolts............

 

[The Yeti]

Awesome. Thanks for the torque sequence and specs there. Good info for anyone who decides to get this done. Anyone happen to know the temp range when checking the fluid? I think the X5 ZF was like between 39-49 C* or something but just going off a distant memory. I assume these would be similar. In the fill, run through the gears, then top off as needed in between the specified temp range and call her a day.

 

[Maximus Gladius]

Awesome. Thanks for the torque sequence and specs there. Good info for anyone who decides to get this done. Anyone happen to know the temp range when checking the fluid? I think the X5 ZF was like between 39-49 C* or something but just going off a distant memory. I assume these would be similar. In the fill, run through the gears, then top off as needed in between the specified temp range and call her a day.

Temp range is 30-50c. Cap it off earlier than later. I cap mine off at 32c.

 

[Maximus Gladius]

Exactly a great way to do pan bolts - be it a SBC 350 oil pan or a transmission pan on a TF998 or these. Half, 3/4, then full. You can't go wrong.

Cleanliness is God in automatic transmissions. As we were taught in class (an entire semester on transmissions and differentials) the clearance between the shuttles/valves in the valve body and the bore wall is a fraction of the diameter of a human hair. A piece of lint from a cotton rag can cause the valve to lock solid. (sadly, I've seen it happen, causing a band servo to bust off the case, literally)
My boss gifted me a custom built work table for automatics - nice slick, smooth steel surface with drain troughs on either side that led to a bucket below and boxes of lint-free rags to use. I pressure washed and brushed off the transmissions before they hit the bench, and I could squeegee the fluid and other stuff to the troughs, and empty the bucket when done. The table stayed clean. Parts were washed up and covered until reassembly because of course it was a shop just off an alley, lots of dust and such in the air.

Some people get lucky working on them in the dirt, but it only takes one time and you have a mess on your hands and a very expensive problem, due to a piece of LINT or hair or dirt that got into the wrong place.

100% on torquing low bolts on pans, heck, even head to block bolts for that matter. Follow the pattern, break it down into at least 2, even 3 stages of "tightening".

I just HAD to pick on the "metal bolt" bit as a person who also deals with chemistry, over 90 of the elements on the periodic table are metals - sodium, calcium, aluminum, indium - in other words, you could have held up a bolt made of sodium (EXTREMELY CAREFULLY) and said it was made of metal.. LOL - yeah, just had to do that! Sorry.

NOTE - those instructions don't mention discarding the pan bolts............

Loved this post. Thanks Bill.

 

[WILDHOBO]

The "kits" that are available have the filter, gasket, O-ring, and fluid.
No bolts.

With that said, refer to the owners manual to verify.

Just checked something and it may be that the PPE pan is thicker and requires a longer bolt, but the PPE comes with new bolts and washers.

It’s so low torque, and they come out extremely easily. I would not hesitate to reuse undamaged factory bolts on the factory pan. We’re only talking about 8-10 ft pounds. Nothing is twisting at that low torque.

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