Big AL have I got a Question For you.........

[dmaxster]

My seal is leaking on my Allison Tranny.......47,000 miles on it to date.....I have talk to some people around here...and they all told me this is very common on the 1000 series transmissions. I don't believe this....not for one min. I have never heard of anyone else having this happen to them.....called dealer and they won't warranty it....so my question to you is....is there really a problem with these seals...or am I one of the few to have it done.....and if so ...would it just be better to have the dealer do the work or can I just do it myself....and be happy with it that way......THanks dmaxster

[BigAl]

dmaxster,

That's a tough question, but I'll try...........

But first, which seal, and how do you know it's a seal. I'll guess it's a front end leak (oil out of the converter housing). There are several places that can generate a leak up there, only one of which is "the seal", which is the converter pump hub seal. Presuming your tranny has run for those 47,000 miles with Zero oil leaks in the front end, that pretty much rules out the other potential leak generaters (porosity in the converter housing, missing OD seal on the oil pump assembly, cocked pump hub seal, etc.)

The torque converter itself can leak if it develops cracks at the lug weld (the lugs are on the converter cover, and that's where you bolt the tranny to the engine). Not all that common, but I've seen it happen.

To answer your question, there has been no particular problem with the pump hub seal on the 1000 Series that I am aware of, although several Dealers have swapped them out trying to fix a front end leak that ultimately was coming from somewhere else. Their knowledge base is the 4L80E and the 4L60E, and if one were to have a front end leak on either of those puppies, the conveter pump hub seal is the most likely culprit.

If indeed the pump hub seal is leaking, this is not a repair I would want to tackle unless you are fairly handy (i.e. almost a mechanic). You gotta pull the tranny, remove the torque converter, pull the seal, and put a new one in (which requires a special tool, unless you are certain you can tap it in and get it square without the tool). Then you get to reinstall the converter..................under normal conditions, the tranny would have been placed on a turnover stand and turned nose-up so that the converter could be "pulled" upward, and reinstalled in the reverse manner. Most do-it-yourselfer's have the tranny sitting on the ground on the oil pan, and reinstallation of the converter in the horizontal position can be lots of fun. THEN, you get to reinstall the tranny in the truck! Again, not fun without all the "toys" the professionals have at their disposal. You can rent a tranny lift at most rental shops, but it's still no fun.

If it were me, I'd take the truck back to the Dealer and ask him to determine EXACTLY what is wrong with the thing (could be something more serious, and you want to know that for sure!!), and then call the local GM Area Service Manager and ask him for some sort of a settlement (follow the Customer Service procedure in the back of your Owner's Manual). You got a lot of miles, but the truck if fairly "young". You may not get anywhere, but it's worth a shot.

Hope this helps! Let us know what you decide, and what you find! smile.gif

P.S. Just remembered this................don't make the mistake another guy did and go to all that trouble to find the engine was leaking either diesel fuel or oil. Whole bunch of work/expense just to find you didn't fix the "real" problem.

[dmaxalliTech]

Dmaxster, Your leak is likely coming from the bolts that hold the first and second modules togather on trans (aka pump bolts) we have seen these leak and GM is aware of a leak in this area, the fix is to remove bolts and install copper washers and a dab of sealer, reinstall and torque to specs. I would call the customer service line and politely ask for assistance, the dealer can do a "goodwill" warr up to 60k, they can cover all or part of repairs with a possible deductable.
Pulling that 450 or so lb trans out is no treat without lift and good jack

[BigAl]

dmaxalliTech,

You are bang-on! smile.gif

dmaxster,

I saw the thread on the converter bolts from another guy's truck being "finger tight" after 30,000+ miles. From a technical standpoint, I have a hard time understanding that one. The bolts are either tight or they're not, and if they're not, I can't imagine it running that long without at least one of the bolts (if not all of them) coming out and banging around in the converter housing. On the other hand, I guess anything is possible.

One concern I would have if this were the case is any attempt to "fix" the thing by simply tightening the bolts. Experience tells me that when two steel parts rub together, they fret. After the parts have fretted, no amount of torque on the bolts will "fix" the fretting, and the joint would have a tendency to come loose again (question is, WHEN!). Worked on one of these years ago in a copper mine in Salt Lake City. We never could get the bolt (in my case, it was a nut) to stay torqued until we machined all the surfaces again and got them nice and smooth like they're supposed to be.

[Jake99Z71]

Hey BigAl,
I had mentioned about 2 months ago about checking your converter bolts. After I found two of mine loose. One had the first three threads rusted and backed out of the converter. The other was just finger tight. My local dealer had seen a couple this way before in the spring of 2001. But they had let the converter loose to damage the front seal on the trans.
On edit was going to metion that I found the loose converter bolts at 40K miles.

[ 02-25-2003: Message edited by: Jake99Z71 ]</p>

[dmaxster]

BigAl.....well I don't know if you want to know but my truck is going in to see what they can do....but I had to go through service support at GM HQ......so they setup the appointment.....but it will be at Broadway Automotive in Green Bay WI ........Tuesday March 4th at 8:30 am ..........my vin # is 1GCHK29142E127067 SO I don't know if you wanted to beable to follow up on it....or not....and the other thing is they said they had to pull it out to look at.....so my ques. is will they fix it or will they pull it out and then let me know what it will take to fix it.....I won't know until tomorrow.....I would like it if you could contact me yet tonight via email and that is madenterprises@itol.com THanks BigAl ...dmaxster....

[ 03-03-2003: Message edited by: dmaxster ]

[ 03-03-2003: Message edited by: dmaxster ]</p>

[BigAl]

dmaxster,

Sorry, but I didn't see your post until this afternoon (Detroit time!) What happened?

I am interested, just a little slow on the draw at times. Don't access the Internet over the weekends much, and I was travelling Monday.

[dmaxster]

well today it went in to see what was wrong with it......so I asked to talk to the tech working on my vehicle....so went into the shop....they had just gotten it out.....so I asked some Q's ....first one was were the t/c bolts loose...yes all but two.....I also mentioned to him that the pump bolts were loose on the exterior .....the one's you can get too easily......he's said that's good to know...cus if those are loose so are the others more than likely.....I won't know anymore than this until tomorrow...after he gets into it more....he wasn't sure who he was going to have to contact....Allison or dealer world.....we left on that note....so maybe BigAl could help :D .....what you think......well when I know more I will keep you informed.....

[BigAl]

Well, at least some of the mystery is solved. If the Torque Converter attaching bolts were mostly loose, it allows enough "wobble" on the torque converter to prevent the pump hub seal from sealing effectively. The seal assumes the converter is turning concentrically to the centerline of the input shaft, seal, etc, etc. If it isn't, hardly any lip-type seal will work.

The other thing I would be concerned about is the Converter lugs.............where the flexplate bolts attach to the Converter. These lugs are welded to the Converter cover, and I've seen instances where loose bolts caused excessive stress on the lugs where the bolts were "tight", and cracked the welds. This can also result in a leak via a crack in the Converter.

The good news is this isn't too tough to fix, but I'd insist on the following.......a new converter, cause most Dealers can't figure out if a crack is present or not, also to make certain the lugs aren't fretted (discussed below). Second, new torque converter attaching bolts (they aren't very expensive). And lastly, I'd want them to check the flexplate to make certain there isn't any fretting at the flexplate-to-Converter lug surface area. In my experience, if fretting exists, you can torque bolts till the cows come home, and they'll eventually loosen up again. The only way to ensure this bolt joint is "as designed" is to make sure the parts are in "like new" condition. Best way to get this is "new" parts.

Hope this helps. BTW, you shouldn't have to fight too hard, cause there is nothing YOU can do, operationally, to loosen these bolts, so this is their problem all the way!

[hoot]

Big Al,

Been difficult getting an answer to this question..

Is there an easy way to check and torque the converter bolts without removing the trans?

[chipper]

hoot:
I saw a thread on here several months ago that indicated you could get to the torque converter bolts thru the starter hole after removing it.

[dmaxster]

yes this is the only way you check them.....it's not F'n easy.....I would have done all this myself if the truck were older...but the possibility of warranty coverage made me decide to take to the dealer......


BigAl.....I had some concerns as far as the converter cracked....they had it sent out and checked....wont' know more until it comes back....they said at least 2 days for this to happen.....I haven't had too much time to talk to the dealer....but yes I am concerned also about the flex plate and the fretting happening....so I will address this as one of the things to have changed or atleast looked at and into......THanks BigAl.....dmaxster (Dave) :cool:

[BobW]

Sounds like this is something that should have a TSB on it. Any idea if one is out?

[dmaxster]

well guys here the report......dealer called back today....truck should be ready for tomorrow pick up....excellant......I asked about the flex plate and the bolts...they said that they were concerned too....so everything will be replaced....also...under warranty......awesome....my day couldn't get any better..... :D then about 5 hrs later dealer called and said we have good news and bad news....I am like alright....truck is done but not covered right....? :rolleyes: ....he said no....truck is done and covered....but it still leaks....so we have to give you a new transmision and this one has to come back out....the bad news....there's not one available....so they don't know how long it'll be....i said that's fine....cus now my ride from the dealer is a 2003 Saab 9.5 ....awesome ride.... :D ......anyways....back to my story.....I got a new tranny out of it....he said there are no rebuilds available so they don't know what is going to happen.....they did a search not a single one around anywhere.....so he didn't know if it would be new or not.....so BigAl it's my Q to you.....you maybe getting this thing.....all info listed above.....you'll have to let us know what you find....and I will keep you posted on how long i wait.....dmaxster

P.S. thank god I didn't decide to this myself..... :D :D :D

[ 03-06-2003: Message edited by: dmaxster ]</p>

[BigAl]

They're gonna have to get one through GMSPO, and I'm pretty sure they have these puppies on the shelf..............got no idea how long it will take to get unit from Grand Blanc, MI to Luxemburg, but I'm pretty sure the boat ride across the Atlantic will be a couple of days, at least. tongue.gif tongue.gif tongue.gif

But seriously, they ought to get one over there pretty quickly. It ain't like you gotta ship from Maine to LA, with bunches of transfers, etc.

I'm really curious now what is causing the leak, cause now we're down to some things that I would have thought would have leaked long before now.......but then again, I wouldn' have guessed the bolts would be loose. Go figure!

Glad you like the Saab................how much can ya haul in the "bed"??? :D

[dmaxster]

well guys.....here it is.....I just got back from dealer.....with the truck.....didn't cost me a dime....they did a "good will" repair for me.....they put a different tranny in it....well gotta love this thing......even though I had a nice loaner.....I still missed my truck.....happy that things worked out......if I had to do it over....I would do exactly what I did.....thanked the dealer for what they did......and told them they will see me again for service......dmaxster :D

[SteveO]

Hoot,

Yes you can check or replace the T/C Bolts without removing the trans...

Access is gained by removing the starter.. There are 6 T/C bolts.. I would replace them even if the OEMs are tight... Part# 11519291 Torque to 44 Lb Ft...
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dmaxalliTech,

In your first post you say to install Copper Washers and a Dab of Thread sealant around the bolts that hold the first (Converter) and second modules (Main Housing) together... Your correct except these bolts are not the Pump Bolts, they are the Bottom four bolts.. The 10 Pump bolts have Rubber washers around them and are in the very center of the trans..

______________________________

[hoot]

Thanks SteveO.

[dmaxster]

so BigAl.....was just wondering if you heard anything on this here tranny that I had.....I would think with a man of your connections would hear something about it.......let me know.....just curious..... :D Thanks again for all your help..... :cool: :cool: :cool:

[BigAl]

SteveO,

Didn't you mean bolt P/N 23049056?????

smile.gif :rolleyes: ;)

dmaxster,

I'll see what I can do. :D

[dmaxster]

thanks bud...... :D

[77TransAm]

Apparently there are lotsa choices for the TC bolt - some better than others.

GM went to production with the 11519291, which has the internal/external hex drive, a pilot on the end before the threads start, but NO locking compound on the threads. This is the bolt that likes to loosen up and cause converter and flexplate failures. I'd avoid it, and if you have your TC bolts out for any reason I'd replace them with something else.

That original bolt was replaced with the 11518919, which has the same physical dimensions (different surface coating, though) and DOES include locking compound on the threads. Haven't heard of any problems with this one losing torque.

Supposedly a new bolt, 11589040, will be released soon. This appears almost identical to the 11518919 with the exception of surface finish. It also includes locking compound on the threads, so it shouldn't have any problems holding torque, either.

If you're getting your bolts from a GM dealer, use one of the GM part numbers listed above. If you're going to an Allison distributor for your parts, ask for 23049056. It's the Allison torque converter bolt, it's been around for as long as the LCT and it doesn't seem to lose torque.

[sonofagun]

77transam,

Do you know when GM shifted from the original bolt to the newer one?

Thanks,
Bob