I went out to my truck this afternoon and noticed an oil spot under the truck. It turns out that it looks to be the transmission lines leaking. I have done some preliminary research it this looks to be a known issue.

With that said, what are most people doing to fix this? My truck is out of warranty and has 52K miles. The only towing is a light single axle trailer and truck has not been modified or abused in any way. I'd rather not pay stealership fees if this is going to re-occur. Does anyone know of a good diesel mechanic/shop around Nashville? Any info. appreciated.

UPDATE: Post #34.

go to a hydraulic shop and show them your line and ask them to build you one. my local shop wants $300 to make me all 3. definetly worth it if your outta warranty. ive had 4 sets replaced now.

Welcome fellow TN guy!

Mine are leaking also.

My mileage is out of warranty myself, but I have had it in once before so hopefully they will take care of me.

If you find a reasonable fix let me know.

mine leak too, deal with it later

I just got my first drip today, at about 20K. It was very cold and on high idle, which I hear makes this problem show up a bit more frequently. At least I knew this was coming, but still...damn, I already miss being able to say I've had NO mechanical issues (not counting gelling). Is there a leaky tranny line club yet? Or is this site the club, lol.

fitting shop..... cost me $117 bucks to fix all three lines....... no more leaks....

yup thats my plan once gm stop doin it for free.

How hard are they to install? About the only thing I've done to it is change oil, filter and fuel filter.

here's the pictures of the finished product

they're not bad to install...... getting them out was a little tough... you just slide back the black cap/clip retainer.... pop off the clips on the ends of the lines and then just pull them out... fairly simple to figure out

Mine leak too. I have no problem adding trans fluid but is there a risk of them blowing apart and leaving me stranded? The dealer wanted $600 to put the same junk back on. I don't think so...

i have not heard of them blowing off. it is pretty amazing they leak that is a pretty crazy fitting.

I thought I read in another post that there was some kind of computer re-program for this also???? Something abouth slowing down the timing on the high idel?
Can any of you confirm this.
I left on the 19th of Dec. for a trip to Cal. and had to have mine replaced as I was pulling out the driveway.

yah the lbz's up here in canada needed a reflash for the tranny. they were burning up trannies when the temp was extremly cold like -40c. the fluid was too stiff to circulate and it was burning tourque converters up. my buddy works way the hell up north and he said they had 35 truck sitting in the lot waiting for tranny work because of the cold snap.

yup i was one of them trucks with a new tranny from last winter... , My truck is still bleeding in my driveway this winter as usual... i think ihave the tranny lines done 5 or 6 times now since i bought the truck in 06..

I just give up,, drive it till she burns to the ground..

just go to a hydraulic shop and get them made up man. save yourself some money. unless the dealer is still paying for them. im on my 4th set now and the dealer says they might not fix them for frww next time.

I have not heard of torque converter lock ups due to the cold weather / leak issue. Interesting, well im part of this club and have had several posts on it. Im still holding out with the free replacements for now. I think I would have a pretty good argument if mine locks up. I have not recieved any notice of a reprogram here. Been a cold MN winter so far. -30F somedays. Anyway, this is a problem that GM has been unable / unwilling to fix since my truck was new and its well documented at my dealer.

its been almost 2 years since the sent out the notices. you had to have it done by a certain date.

i just had mine done a few weeks ago.... i think on a recall there's no time limit it's just whenever you get it done..... you are right about these trucks smoking the transmission at temperatures lower than -40 degrees but there was and is a recall that fixes that problem.... the TCM from factory is programmed so that when the mercury drops below forty it stops circulating the trans fluid through the cooler, it's not that it gets too thick to circulate it's just that the truck stops circulating it..... and when your truck sits there and idles on high idle all day with the fluid not circulating it heats up and cooks your transmission.... but the recall from the dealership changes the TCM program so that it circulates the fluid all the time and fixes that problem

4 sets and so far so good on the 4'th set, All under warranty.

i just had mine done a few weeks ago.... i think on a recall there's no time limit it's just whenever you get it done..... you are right about these trucks smoking the transmission at temperatures lower than -40 degrees but there was and is a recall that fixes that problem.... the TCM from factory is programmed so that when the mercury drops below forty it stops circulating the trans fluid through the cooler, it's not that it gets too thick to circulate it's just that the truck stops circulating it..... and when your truck sits there and idles on high idle all day with the fluid not circulating it heats up and cooks your transmission.... but the recall from the dealership changes the TCM program so that it circulates the fluid all the time and fixes that problem


yup kinda like what i said

almost.... but not at all.. you stated that the fluid was too thick or cold to circulate and that is not the case at all.... in fact the fluid was fine just the tcm stops circulation in extreme cold temperatures... and this re-program allows the fluid to circulate all the time as opposed to it shutting off after a certain temp

touche!

i was only kidding

Are these lines leaking at the radiator/tranny cooler?? If so, I know some fittings, that converts the straight 5/8 lines to a screw on fitting. I don't think I can list the site of the forum, but I can send the info via PM if you are interested. And these are made for the Allison tranny. Cost is under $11 a fitting too.

no they're not leaking at the actual fittings.... the three lines have a section of how in them in the middle and on each end of the shitty chinese crimped hose fitting they leak

Same problem here. Out of warranty as well. But I took it to chevy and asked for a policy repair. The part is on National back order which tells you that your not alone. They know its happening to all of them.

The dealer fixed mine for free.

Good luck!

Give Mike L. a call. Inglewood Trans. He's a vendor and has a fix.

Mine are leaking once again, real sad how after all these years the tranny cooler lines still leak on these trucks. My 98 was the same. :mad:

I want to make up something myself but not sure what kind of fitting is @ the tranny and rads. Guess one of those remove and look into it deals..

check the beginning of this post..... i have pictures showing what i did

I went out to my truck this afternoon and noticed an oil spot under the truck. It turns out that it looks to be the transmission lines leaking. I have done some preliminary research it this looks to be a known issue.

With that said, what are most people doing to fix this? My truck is out of warranty and has 52K miles. The only towing is a light single axle trailer and truck has not been modified or abused in any way. I'd rather not pay stealership fees if this is going to re-occur. Does anyone know of a good diesel mechanic/shop around Nashville? Any info. appreciated.
I'm looking into a few options now. Where are you in TN/Nashville ? Depending on what I find/do I might be able to send you to the same place.

here's the pictures of the finished product

where did u get that done at i live near by

almost makes me wish i hadn't left Alberta...those are nice looking lines Carl. Where did you get em built.?? Greenline or someone like that.?

You say you removed the original lines your self..would you consider to help a great many of us here by possibly doing a DIY with pics and posting it here..?? I do believe that would be a huge help to many..self included.! and of course a service to the right kind of mankind too..!!

Thank you,

stk

I'd appreciate it too if someone would do a DIY. I'd put it in DIY.

JD,
Yes, I am in Nashville. As an update to my original post, I took my truck into Jim Reed Chevy yesterday. It turns out that on the way there, my SES light came on as well (how timely). I thought this was related to the trans leak. However, upon inspecting this, Jim Reed called me and told me it was P0403 (EGR cleaning code). Jim Reed wanted $400+ to fix (clean and clear code) this and to perform the hose change that ran from the radiator for the tranny. I ended up talking to the Service Mgr about wanting to charge me this and spoke with a GM rep. about getting it covered under warranty. He called me back and told me GM would cover everything. I was appreciative of this gesture. Therefore, I took my truck home last night and on the way back to work this morning, my SES light came back on!!! I called them back this morning and took it down there. At this point, I think it is the EGR issue once again and I'm hoping they replace the EGR motor. I don't know what/if they will charge me yet. My truck is completely stock and I have not done one thing to it.

With all of the above said, it's frustrating to purchase this expensive of a truck and have it have issues. I ended up writing Rick Wagoner and pointed him to some threads on here relating to the tranny hoses leaking. Not acceptable in my book...

JD, if you would, PM me the place you are thinking about? I wouldn't mind finding a good mechanic that is reasonable and trustworthy.

I'm looking into a few options now. Where are you in TN/Nashville ? Depending on what I find/do I might be able to send you to the same place.

JD,
Yes, I am in Nashville. As an update to my original post, I took my truck into Jim Reed Chevy yesterday. It turns out that on the way there, my SES light came on as well (how timely). I thought this was related to the trans leak. However, upon inspecting this, Jim Reed called me and told me it was P0403 (EGR cleaning code). Jim Reed wanted $400+ to fix (clean and clear code) this and to perform the hose change that ran from the radiator for the tranny. I ended up talking to the Service Mgr about wanting to charge me this and spoke with a GM rep. about getting it covered under warranty. He called me back and told me GM would cover everything. I was appreciative of this gesture. Therefore, I took my truck home last night and on the way back to work this morning, my SES light came back on!!! I called them back this morning and took it down there. At this point, I think it is the EGR issue once again and I'm hoping they replace the EGR motor. I don't know what/if they will charge me yet. My truck is completely stock and I have not done one thing to it.

With all of the above said, it's frustrating to purchase this expensive of a truck and have it have issues. I ended up writing Rick Wagoner and pointed him to some threads on here relating to the tranny hoses leaking. Not acceptable in my book...

JD, if you would, PM me the place you are thinking about? I wouldn't mind finding a good mechanic that is reasonable and trustworthy.

Have you every had the EGR update? That could be part of your EGR problem.

As far as the tranny line issue, I don't think GM has a fix yet. So, it maybe going back again in a few miles. :(

Have you every had the EGR update? That could be part of your EGR problem.

As far as the tranny line issue, I don't think GM has a fix yet. So, it maybe going back again in a few miles. :(

Service Bulletin:#08-07-30-049: Transmission Oil Cooler Line Leak (Replace Affected Cooler Line) - (Dec 12, 2008)

"If the under vehicle inspection reveals transmission fluid leaking from one of the cooler lines, replace the affected cooler line. New transmission cooler lines have been released to address this concern. These new lines have been manufactured with an updated crimp process to better withstand the cold temperatures. Refer to SI for the replacement procedures."

New Part Numbers:
20759971 Pipe Assembly, Trans Fluid Cooler (Upper/Outlet)
20759972 Pipe Assembly, Trans Fluid Cooler (Lower/Inlet)
20759973 Hose Assembly, Trans Fluid Aux Cooler Inlet

Service Bulletin:#08-07-30-049: Transmission Oil Cooler Line Leak (Replace Affected Cooler Line) - (Dec 12, 2008)

"If the under vehicle inspection reveals transmission fluid leaking from one of the cooler lines, replace the affected cooler line. New transmission cooler lines have been released to address this concern. These new lines have been manufactured with an updated crimp process to better withstand the cold temperatures. Refer to SI for the replacement procedures."

New Part Numbers:
20759971 Pipe Assembly, Trans Fluid Cooler (Upper/Outlet)
20759972 Pipe Assembly, Trans Fluid Cooler (Lower/Inlet)
20759973 Hose Assembly, Trans Fluid Aux Cooler Inlet
These #'s have been out for a while. The ones that have them state they aren't any different. Still leak.

JD,
Yes, I am in Nashville. As an update to my original post, I took my truck into Jim Reed Chevy yesterday. It turns out that on the way there, my SES light came on as well (how timely). I thought this was related to the trans leak. However, upon inspecting this, Jim Reed called me and told me it was P0403 (EGR cleaning code). Jim Reed wanted $400+ to fix (clean and clear code) this and to perform the hose change that ran from the radiator for the tranny. I ended up talking to the Service Mgr about wanting to charge me this and spoke with a GM rep. about getting it covered under warranty. He called me back and told me GM would cover everything. I was appreciative of this gesture. Therefore, I took my truck home last night and on the way back to work this morning, my SES light came back on!!! I called them back this morning and took it down there. At this point, I think it is the EGR issue once again and I'm hoping they replace the EGR motor. I don't know what/if they will charge me yet. My truck is completely stock and I have not done one thing to it.

With all of the above said, it's frustrating to purchase this expensive of a truck and have it have issues. I ended up writing Rick Wagoner and pointed him to some threads on here relating to the tranny hoses leaking. Not acceptable in my book...

JD, if you would, PM me the place you are thinking about? I wouldn't mind finding a good mechanic that is reasonable and trustworthy.
Hey bud, fill out your signature so we know what we're working with. I don't have a shop in mind to do the work; I do all my own stunts ;). I was meaning a place to make the hoses. Then I'll do my install.
Waller Sales in White House Makes all our excavator hoses and before long I'll buy some OE hoses and have them fix the rubber sections.

i got my hoses done at greenline hose and fitting in edmonton alberta, they had all three ready to go in about a half an hour and only cost me about 120 bucks... but basically any hose and fitting shop would be able to do the trick probably... i'll probably be back under the hood of my truck in the next day or two and i could take a few pictures to show and explain what i did to remove them...

That would be awesome Carl. I kinda figured greenline, used to go there lots in Calgary in the Foothills Ind park. 61st Ave SE. Great place for anything realted to hose and hydraulic lines/fittings & damned good pricing on REAL Rubber garden hose.! Not that cheap chinese plastic crap from Home Depot that won't even bend in the summer time let alone in winter..!!.

If you add a parts list to that DIY, would be great as well.

Thank you and I look forward to seeing it. Take your time and do us all proud..!!
...stay warm man.

Stk

Any news on this.? I guess a bump was in order...especially for a DIY that would help a lot of people.

stk

yea... not yet i'm just in the bush crawling around in the snow here for a while haha but i'll do my best as soon as i get back home in the shop to get up some pictures and info

looking to bring this back from the dead. Any new news? Any replacements that are worth a flyin flip? My dad's 07 Classic just experienced this wonderful issue at 25K mi. Not too happy about it either. Is there a revised service bulletin, or just the one mentioned in post 36?

http://www.dieselplace.com/forum/showthread.php?t=202078

Would really like to see that DIY fix for this problem.

Got one crimp leaking good now at 38,000 miles.The steel lines are actually 16mm outside diameter,a bit smaller than 5/8.Checked out tha SwageLok tubing connectors which are available to fit over the 16mm tubing and with a variety of ends in the half inch size to adapt to hydraulic hose ends.The factory hose is 5/8 i.d. crimped over the 16mm tubing.Wonder if the reduction to 1/2 inch for less than a foot will really matter?The Swageloks have a double ferrule,one for locking and one for sealing and are available in carbon steel or stainless steel.What kind of temps is the hyd. hose gonna have to stand up to?