Allison MD3060 Filter Bolts Stripped

WiredForStereo · 06-15-2021, 02:05 AM

I changed my fluid and filters on my MD3060 today, which by the way, is doable for a normal person, though not for the faint of heart, it's a bit more than car. I am a big proponent of fresh high quality synthetic lubricants in everything.

So I got the fluid drained, filters out, new O-rings, new filters on, and went to bolt everything back in the bottom of the transmission housing, and behold, three of the filter bolts are completely stripped out. I noticed when putting one of the bolts in by hand, that it didn't want to go, so I pulled it out and inspected it only to find aluminum threads on it. Tried again, same thing happened, tried again, it went in smoothly, only to strip out when torqued. So it seems obvious that the tech who did this last time screwed it up and either didn't notice, didn't torque it properly, or just left it for someone else to deal with.

All the other nine bolts torqued up to spec, which by the instructions, I think was 35 ft-lbs, or whatever it was, I always do the lowest on the spec range, unless something is leaking. I have found that's generally the best rule for aluminum, only tight enough to not leak.

Has anyone here ever had this happen?

Off hand, the fix is generally Heli-coils for this sort of thing. But it is a deep hole and a lot of drilling in a new machine is not always advisable. I'm going to do some more research. Surely this is not the first MD3060 to have threads stripped, and if it's a decent machine, it should be designed to be repaired.

WiredForStereo · 06-15-2021, 07:05 PM

All the information I can find seems to indicate that the pro kit is simply a Time-sert kit with the 24mm inserts and with an extra drill guide.

Considering that is around $1700, it looks like I'm going with the Time-sert kit and the 24mm inserts for $120.

If I can manage not to screw it up too badly, this should work and be reasonably professional.

It does seem to use shallower bolts, which is not really mentioned anywhere in the literature. So I'll buy new shorter bolts to match.

Didn't get any replies on this, so it seems this is a rare problem, or one people throw money at at the stealership. I will report back when the repair is complete.

cadillackid · 06-15-2021, 08:55 PM

thread inserts arent bad.. ive used them before.. just make sure you drill absolutely straight and with a high quality drill bit.. I usually drill pretty slow in aluminum..

you want to make sure you extract ALL metal shavings.. even a single metal shaving stuck in a valve or in a check-ball cavity will wreak havok a shaving or two in the pan isnt so bad as the filters take care of those.. but since you are working in an area around the filter housing presumabley with the filters out you need to clean up well.

Bus'n it · 06-16-2021, 09:35 AM

Curious, do you have any pictures? I've reached the point of my life where oil changes are preferably left to a "professional" shop to deal with. Been there done that and have all the merit badges! That said, if someone stripped the bolts in the past, I would be left with a large bill I'm sure.

WiredForStereo · 06-16-2021, 03:56 PM

Quote:

Originally Posted by Bus'n it

Curious, do you have any pictures? I've reached the point of my life where oil changes are preferably left to a "professional" shop to deal with. Been there done that and have all the merit badges! That said, if someone stripped the bolts in the past, I would be left with a large bill I'm sure.

I don't have any pictures, nothing to see really, I mean unless you want to see a picture of a perfect set of aluminum threads sheered off and removed from a hole.

I like to do my own maintenance, it's much cheaper and I seem to have ridiculously bad luck with stealerships.

Just last week, they had my work truck for three days and DIDN'T DO THE RECALL! Plus, they changed out my brand new expensive synthetic oil and filter for whatever the Ford factory garbage is. I am still angry.

Nobody cares about my stuff like I do.

WiredForStereo · 06-16-2021, 10:10 PM

Okay, I'm not paying attention.

The first instruction is to remove the control module, which is the whole bottom of the transmission.

So I might as well do all of them while I'm in there, or maybe have Allison do it. I at least need to get a price.

My main concern at this point is getting the inserts less than straight.

Also, I'll need a new gasket. Probably.

WiredForStereo · 06-17-2021, 03:32 PM

I just talked to my local Allison shop, they quoted me $2400, which is effing ridiculous. Well, never say no without a price.

So I got the Time-certs in today, and Allison has the gasket, or what they think is the gasket. Just need to go get the gasket and buy a transmission jack from Harbor Freight, and we can get this thing moving.

Maybe I will also get some heavy duty jack stands so I can get this thing up a little to work on. Because I'm big boneded.

I'm just going to do all 12 of them and be done with it. Though the kit I bought only has 10, so I bought another one which will be here Saturday.

Anyone have any tips for drilling straight in? Some sort of sleeve? I guess I could make a guide with the drill press. That would help.

WiredForStereo · 06-18-2021, 11:22 PM

Got the control unit off. I had thought that it was only 3-4 bolt holes that were stripped. But all of them showed at least some damage, some well into stripping out. I was planning on putting inserts in all of them anyway because I didn't want to do the job again in case another one stripped out. All the bolts including the control unit bolts had red Lock-tite.

Also discovered that the external plug for the internal wire harness was broken. This isn't a fatal problem. Can be worked around as it was, they had it zip-tied together. I will check how easy it is to get a new one first thing Monday morning because conveniently neither of the Allison qualified people work in the parts department in the evenings.

I'm documenting this in case something like this happens to someone else in the future, since I was unable to find much help on the forums about it.

Changing the filters is a doable job for anyone who can change oil, and can use a torque wrench. And I recommend doing that according to Allison's schedule, 3-4 years, 75k miles or whatever, I don't remember off hand. Just change it every 4 years and call it good. Don't screw up the bolt holes, 38-42 ft-lb of torque. I recommend sticking to the 38 end. There are multiple YouTube videos on how to do this. Get the Allison kit, it includes filters, gaskets, and O-rings.

Fixing the bolt holes involves pulling off the control module which weighs 60 lbs. A transmission jack is suggested, but I did it with just a floor jack. Power wash everything first, you're not going to miss the grime. I would have, but I didn't feel like laying in a puddle all afternoon since I can't move the bus, and I need this done this weekend because it's blocking my driveway, which also cripples my business.

You have to pull the safety clip on the top of the harness and pull the whole rest of the harness through the hole, which is a dumb design, but it is what it is.

This YouTube video will show you which bolts to pull, pay close attention, he removes one more right at the end.

https://www.youtube.com/watch?v=UIpoKwzUc8o

Then you have to drill out the holes. I made a guide with a thick piece of high quality epoxy plywood I had laying around and a drill press, so the holes would be as straight as possible. This was to avoid the need to buy the $1700 kit to do the same.

Then I tapped the holes with the included tap in the $100 Time-sert kit you can get on Amazon: https://amzn.to/3xsuhvm (affiliate link).

Then you'll need two of the 24mm insert kits, which cost $21 each: https://amzn.to/3gEmzJ5 (affiliate link). You will also need the gasket which you can get at your local Allison parts supplier for around $30. Also available online, just search for "Allison MD3060 Control Unit Gasket."

Other than some issues with the wiring harness (remember to remove the safety clip) everything has gone more or less smoothly, though lots of grime got into the control unit from the dumb wiring harness configuration, I'll have to clean it out really well. I have done six of the holes so far. The kit works as promised. Just get the holes straight. The drill bit does bite too hard, it just goes straight in like a screw, leaves the hole a little jagged, but the tap works properly, and the inserts do also, leaving a nice clean steel threaded hole.

Though the official kit is a Time-sert kit, an enterprising person could use Heli-coils instead. They're not as pretty, but the pull-out strength is slightly better for the same depth. And they are much cheaper. In this case, you'd probably have to put three coils in each hole for the same thread depth. I used WD-40 for thread cutting oil.

So, all told, it's probably going to be 10 hours, same as the shop, but $170 (plus some of your own tools) instead of $2400. I recommend doing it on concrete instead of gravel. It will make everything so much easier.

magnakansas · 06-19-2021, 01:16 AM

35 ft-lbs is pretty good sized bolt... most of the automatic transmissions I have worked with, filter and valve bodies were more in the area of 35 in lbs......I do not have the allison books to work with but I ask this so that you might look at the numbers again and non allison reference charts so as to make certain correct torques are being used. factory manuals have mistakes sometimes....

william

WiredForStereo · 06-19-2021, 02:03 AM

Quote:

Originally Posted by magnakansas

35 ft-lbs is pretty good sized bolt... most of the automatic transmissions I have worked with, filter and valve bodies were more in the area of 35 in lbs......I do not have the allison books to work with but I ask this so that you might look at the numbers again and non allison reference charts so as to make certain correct torques are being used. factory manuals have mistakes sometimes....

It's actually 38-42, and that's the standard Allison spec, as confirmed by every source I have found. It does seem high, but that may be due to the length of the threaded portion, about an inch. I have found varying numbers from 28-55 depending on the bolt, lubrication, etc.

Interesting new thing I just learned, the first thread takes about 35% of the force, and after the 6th thread, nothing. So the stronger the bolt, the less stretch, more force is shared between more threads.

That intuitively leads me to believe that these are pretty stiff bolts by the design, long threads, large heads.

Coincidentally, all the bolts that hold on the control module are about the same construction, though of different lengths.

WiredForStereo · 06-19-2021, 02:05 AM

Thought I'd share some pics.

My new phone produces massively large images and this site doesn't handle them, but if I upload them to Facebook first, then re-save them, it makes it easier to post them here.

In the second picture, you can see the threads in various states of stripped out, bottom left is completely stripped out, smooth like it was drilled.

Note the darkish but still red ATF dripping out of the transmission, but sitting in the sun, it turned purple.

joeblack5 · 06-19-2021, 07:04 AM

How much extra depth is in the hole? Can you tap deeper and use a longer bolt?
Are these M12*1.5. Can you go up to a standard size bolt like a 1/2" ?

You also could thread and glue a stud in and use a nut on the other side..

All maybe unconventional..but then..converting buses is as well.

Good luck
Johan

WiredForStereo · 06-19-2021, 11:17 AM

Quote:

Originally Posted by joeblack5

How much extra depth is in the hole? Can you tap deeper and use a longer bolt?
Are these M12*1.5. Can you go up to a standard size bolt like a 1/2" ?

You also could thread and glue a stud in and use a nut on the other side..

All maybe unconventional..but then..converting buses is as well.

These are M10x1.5. The inserts may be M12, but I don't know.

There is not much extra depth in the hole, maybe a few millimeters, so I don't know if there is enough space for the next size up.

According to the official instructions, if the hole is too wallered out for an insert, the transmission case must be replaced.

And let's be honest, a used MD3060 is well cheaper than either the $1700 kit or the $2400 repair bill.

WiredForStereo · 06-21-2021, 02:05 PM

The transmission is back together as of late last night.

I am a little gun shy about tightening all the way up to 38 ft-lbs, so it's only at 35 presently. You never know when they are lubricated and whatnot. My rule for aluminum is only as tight enough so that it doesn't leak.

Interesting, thing, one of the bolts was missing from the factory. Empty threaded hole, never been used.

I also consulted the maintenance log, and it appears that the only things that have ever been done to this transmission since the factory was the 10k mile service which was done at 92k, and the 50k service which was done at 145k. As far as the fluid, all it said was "ATF HEAVY DUTY" so take that for what it's worth.

Everything looked nice. The fluid was still nice and red, with just a hint of brown, no evidence of water intrusion or clutch failure. Only a dusting of metal on the drain plug magnet.

This afternoon, I'll be refilling it and getting on with the next thing.

So if anybody needs help with this fix in the future, or anything I can offer experience on, just leave a message here or in PMs. It's not easy, but it's not bad. Do change your fluid and filters every 4 years minimum or according to fluid analysis, do not over torque your bolts, do not use an impact.

cadillackid · 06-21-2021, 02:59 PM

nice work!!! taking down the valve body of a trans isnt for the faint of heart.. im assuming that is what you dropped was the valve body.. the seals and any check-balls are the most important part, howerver on that trans if I remember right the valve body can come down as a unit so you dont have check-balls to deal with.

I just went through the bolts in aluminum thing swapping the HPOP in my T444E... the engine front cover is aluminum and the HPOP and its reservoire bolt into it.. the one thing I note is when I thread a bolt in how many turns did it make.. in my case even though the torques are fairly stout.. the bolts thread far into the mating cover.. it was a lot like 12 turns of a fine thread bolt.. if I only have a few turns I get leery of pulling a lot of torque on it.. most of the transmissions ive worked on, the bolts thread pretty deep ..

WiredForStereo · 06-21-2021, 05:31 PM

Quote:

Originally Posted by cadillackid

nice work!!! taking down the valve body of a trans isnt for the faint of heart.. im assuming that is what you dropped was the valve body.. the seals and any check-balls are the most important part, howerver on that trans if I remember right the valve body can come down as a unit so you dont have check-balls to deal with.

It's called the "control unit." It includes all the valves with their solenoids or whatever actuates them and two sensors, all of which connect to a wiring harness which exits through an upward facing surface on the turbo side (this is a pusher bus). It is quite nice and well designed (except for the plug) with the fluid passages even labelled in the casting as to which clutch they belong. So that was neato.

Coincidentally, for those of you with an Allison with 6th gear locked out, that means your #4 clutch is only used on second gear, IIRC. Or one of them is, only used on second gear.

Quote:

Originally Posted by cadillackid

I just went through the bolts in aluminum thing swapping the HPOP in my T444E... the engine front cover is aluminum and the HPOP and its reservoire bolt into it.. the one thing I note is when I thread a bolt in how many turns did it make.. in my case even though the torques are fairly stout.. the bolts thread far into the mating cover.. it was a lot like 12 turns of a fine thread bolt.. if I only have a few turns I get leery of pulling a lot of torque on it.. most of the transmissions ive worked on, the bolts thread pretty deep ..

I never had to do anything to the HPOP on my 7.3. I did replace the injectors and glow plugs, as well as one of the wiring harnesses under the valve covers. Also the water pump. From what I understand of the 444, the HPOP is bolted to the back side of the front cover, the front side of which is where the water pump lives.

This lesson I have learned about how bolts stretch and put pressure on threads has been tickling my brain. With a long enough thread, you can have the 1st thread completely stripped and the last thread properly torqued. I wonder if there is a wear component.

Obviously, the proper way of doing it is with steel inserts. My family motto is "If it's worth doing, it's worth overdoing."

cadillackid · 06-21-2021, 06:05 PM

C4 is only used in 2nd and 6th.. the C4 clutch typically takes a beating ,the C4 clutch is the one people tend to try and tighten up in a 1-2 shift to get that "hard shift" feeling so they run the Trim up high which makes C4 come on faster and stronger.. dangerous game it is trying to make an allison shift hard.. (guys like that hard-shift hot rod feel thats so easy to achieve in a 4L60E.... in that trans you just put in a corvette server, turn up the TV pressure, and block the 1-2 accumulator.. so you bring the 2nd gear band on instantly.. allisons dont have any bands.. bands are a lot of times the failure points in other trannies so allison doesnt use them.. I miss building TH350/700/4L60(E) variants.. the days of tire screeching hard shifts!! yeah!! no way ill do it n an allison or even try!

then again those were days of stripping out sun-gear shells and scattering planet gears on the track too!!

WiredForStereo · 06-21-2021, 09:17 PM

I don't have any need for any sort of hard shift.

I want whatever makes it last the longest so I don't have to deal with it. That's why I use synthetic lubricants and stuff like bypass filters.

alpppppp6 · 07-07-2022, 11:10 PM

Hi,
My Allison 3K Trany dip stick tube was leaking, I put a new tube gasket to fix that. During that process it leaked out near 2 gal oil. So I went ahead with filter and oil change. I am glad I went with it, the filters I removed had a 2012 date stamp on it, 10 years old. Tonight I installed the new filters but I did not put in the new oil yet. I have one striped bolt

. Now what? The way I installed the bolts with the torque wrench I start at 24 ft-lbs on all bolts then go up to 38 ft-lbs. All the bolts are good but that one is at 24-30 ft-lbs is just spinning so it must be stripped. I did not pull it out, just sitting in there. My question is, if I leave it like that, put in the oil and see if I get lucky for a while, maybe it will not leak. Is it safe, is the bolt housing has anything to do with oil passage? I mean can the stripped aluminum particles get in to transmission and do more damage. I will eventualy fix the stripped bolt hole but I wonder I can get a way with it for a while? Thank you, Al

WiredForStereo · 07-08-2022, 12:10 AM

Quote:

Originally Posted by alpppppp6

Is it safe, is the bolt housing has anything to do with oil passage? I mean can the stripped aluminum particles get in to transmission and do more damage. I will eventualy fix the stripped bolt hole but I wonder I can get a way with it for a while?

If it's only one bolt, you may be able to get away with it for the time being. It may start to weep on you, it may warp the cover.

I don't think the particles can get back in.

Best practice would be to repair the threads like I did above, but it is a chore. I'm glad I did mine all at once so I never have to do it again. But it will probably work for a while, maybe even a long while. Your mileage may vary.

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