'06 Exhaust Manifold Gaskets, Replacement

[PBrauer]

'06 2500

Stock turbo and manifold

Jacobs/Cummins e-Brake



#6 exhaust gasket is leaking. Not terribly bad but I need to do something about it eventually. It doesn't look bad but I can now hear it inside the cab. When I do this, it'll be in a parking lot somewhere. I have 50 ft-lb (non-ratchet) and a 250 ft-lb (ratchet) torque wrenches. I also have a Factory Service Manual on my notebook. I've read through the procedure several times already.



I have six new manifold gaskets, two new turbo gaskets, and one of each "type" studs and nuts just in case I damage one. I'm a capable do-it-yourselfer but haven't ever removed a manifold.



First and biggest question is what things will hang me up in the middle? Any and all tips about things that might sneak up on me in the process would be greatly appreciated. I get nervous any time the truck isn't running since I basically live in it.



How much and how many times should I soak the studs (PB Blaster)?

What are the odds that simply re-torquing will help for now?

How much "added" torque is safe?

Loosen then re-apply or just add a little?



FSM has you remove the Turbo completely. Is this really necessary?

If the turbo can stay, can I also leave it bolted to the manifold?

Is there any chance that I could back all the studs out enough to swap one gasket at a time... turbo bolted/unbolted?

Will the gaskets come off/out clean or will I need to scrape them off?



No lift... How hard are the two "bottom" nuts on the turbo to remove?

What's better/easier, on my back with extensions or from the top/side?

If extensions... anyone remember how many (length) it took to reach?



I plan on removing the intake. Is it worth the time to remove anything else, including the battery, tray, etc? I don't care if it takes all day as long as I know I can get through it.



TIA

 

[HBarlow]

The exhaust manifold gaskets on my high mileage '06 failed recently and also on a fellow transporter's high mileage '05. My friend's '05 ran for awhile before he realized anything was wrong with it and the delay resulted in a warped, ruined exhaust manifold and two broken studs. My advice is replace the gaskets asap to avoid the problems he had.



I am not a mechanic. I had a friend who is a mechanic replace my gaskets. If memory serves me, he replaced each one individually by backing off the nuts and sliding the manifold out away from the head. He made it look like a simple job but the locking hardware on one or more studs made the job tedious.



Harvey

 

[DPKetchum]

Bet the manifold warping is the reason the gaskets have failed to start with. The longer a inline engine is the more common this is. Thats why aftermarket manifolds and big equipment have manifolds that are multi sectioned.

 

[HBarlow]

Bet the manifold warping is the reason the gaskets have failed to start with. The longer a inline engine is the more common this is. Thats why aftermarket manifolds and big equipment have manifolds that are multi sectioned.

Not true in my case. My manifold is fine with new gaskets. No leaks. I think 200k miles of hard pulling over mountain passes, countless heat and cool cycles, and some vibration allowed the nuts to back off slightly and create a leak.



My friend continued pulling heavy trailers over the mountain passes before he heard or recognized the exhaust leak and for an additional period before mine failed and I was able to tell him he probably had the same problem as my truck.



Each to his own but I tend to have more trust and confidence in the Cummins engineers who design, build, test, and market the engine and its many components than I do the aftermarket companies who sell parts for the Cummins engines. Cummins has a long public history of building million mile engines for the trucking industry. Their engines and components are not always perfect but I believe that they do their best to produce durable engines and components and also that they refine and improve components that prove less than durable.



Harvey

 

[PBrauer]

Direct experience, 2nd opinions please...

... If memory serves me, he replaced each one individually by backing off the nuts and sliding the manifold out away from the head. He made it look like a simple job but the locking hardware on one or more studs made the job tedious.



Harvey

Harvey, thanks.



This is exactly what I'd like to do. They are all studs but some are threaded on both ends of the hex to hold the heat shield and a bracket for a coolant tube. Between the hex cap and the manifold itself is a spacer so with a little patience this method seems reasonable.



Here's what I'd like to do:

1) Remove air box, heat shield, and cab heater return line

2) Loosen all twelve studs

3) Remove spacers two at a time and re-start the studs

4) Carefully pull the manifold away from the head

5) Remove studs in pairs, replacing one gasket at a time

6) Move manifold back toward head

7) Reinstall spacers in pairs

8) Torque studs and finish up



Can anyone confirm that the manifold will move out a little if I do it this way. I'm worried that it will either be semi-rigid from the turbo or the gaskets will be stuck. If it doesn't want to move I won't know which is holding it... . main question is whether the turbo will move a little if I CAREFULLY pry on it (manifold) then pull it outward??? I plan to use bungees over the fender to hold it out while working the gaskets.



I know it's only four more nuts to get the turbo loose but those back two look like a royal PITA and I'm worried that it'll be equally hard to get it lined back up.



I'm sure it'll seem easy once I'm done but I really need to over prepare since it's cold outside. I have very few resources (broke) if I can't get this done myself.



Can anyone else chime in to back up what Harvey's friend did and whether or not I'm missing anything else?



I was tempted to use the 911 forum for this... I'm either getting paranoid or the rushing air sound has gotten worse over the last few days or weeks. I'm sitting in Port Jervis, NJ right now, headed East all the way to Eastern Newfoundland (transporter). I lost my alternater last weekend, hit my first deer Wed or Thurs night, installed an aux lift pump in a truck stop (FP was down to about 5psi with a fairly new pump module), and I think I might be losing rail pressure or my FCA... rough idle and low power that comes and goes. About a month ago I heard my first terrible screech when I came OFF of a heavy throttle. Thought I'd lost the turbo but from reading in here, it might very well have just been that gasket...



I'd really, really appreciate some help here. It's been a long couple of weeks. I left out a few other things. Hitting that deer is a story in itself. Bumper stopped right at the condensor. No grill damage. Lot's of cracks in the facia but nothing came off or is ready to come off. It's a miracle I'm not down already. Luckiest unlucky day I've ever had... hit her dead center at speed pulling a 31' TT and she probably weighed 120 or so. I've dodged so many... just couldn't miss this one. She came from the left, running full speed. Guess that's why she didn't go under the truck.

 

[DPKetchum]

There was a design change in the manifold in the past year or so. Some added metal to a few areas of it because of warpage and cracks. The aftermarket manifolds in this case are of heavier duty metal and are three piece to allow for exspansion during cool down and hot cycles. The rear of these motors are the most heat. Usually the reason the nuts get loose is the manifold has grown and shurnk many many times. On some you'll find rear nuts broke off and the holes in the manifold and head won't match up. As long as it goes back togather ok. I would NOT use old bolts again.

 

[PBrauer]

So would it be a good or bad idea to try re-torquing just the two #6 studs?



It didn't occur to me that they might have loosened.

I don't want to break them if they've been stressed either.

Wish I'd bought more spares.



#6 is the last one in the torque pattern and I do have the right studs (the two new ones).

Maybe I should try just replacing those two studs for now and see what happens???



Really wish I'd bought a full set...

Think I will for the full change if I can.

 

[DPKetchum]

You could try retoquing them but I would NOT use old bolts/studs cause of stress. Your correct. Just do the leaking ones on a retorque and only torque the ones your installing. Don't fool with any others and see if leak stops before going any further. You can always start again with if needed.

 

[Forrest Nearing]

I was going to say try snugging them back up. did this when an ATS manifold started leaking at #6

 

[HBarlow]

I think it would be a very bad idea to try to retorque the existing studs. I'd bet they'll break. On mine and my friend's (fellow transporter) truck the gaskets came out clean, no evidence of sticking to head or manifold.



You might get away with replacing gasket and studs at #6 only but I don't think it is that much more difficult to replace them all using the procedure you described above.



I just called my mechanic buddy who replaced my gaskets. He was a line mechanic in a local Dodge dealership for years before he left for a different type of mechanic job.



I verified the procedure he used.



Remove the airbox and other miscellaneous parts for access as you suggested.



Leave the turbo connected to the exhaust manifold and loosen all studs and slip the exhaust manifold back away from the head but leave it resting on the studs.



Remove the studs in pairs (carefully to avoid breaking) and replace each gasket separately. Replace the two studs closest to the leak using extreme care and lots of PB Blaster first to get the old ones out.



Put it back together and torque carefully.



Having just finished 2yrs, 9 mos and 385k miles on the road as a transporter myself, I sympathize with you.



Best wishes on a painless repair. If you run into trouble pm me. I am not an expert and can't bail you out but I'll give you the cell phone number of my mechanic friend. He'll take your call and help you if needed.



Harvey

 

[PBrauer]

Thanks Harvey (everyone else too). Thanks especially for making that call, which answers about 90% of my questions. I'm going to look you up someday and buy you a buffet for old times sake... I did notice the keyword "finished". Hope things are going well for you now. Thank your friend for me too. I should have enough FJ coupons to buy all three of us a buffet if we all drink water... (I sure hope that's actually funny). I really am grateful.



I was typing (after post #8) when others were posting. Things are getting clearer now but I'm going to post it anyway. I'm thinking I will replace the two studs now (or soon) then get a full set of studs before I do any of the gaskets.



=========

Thanks DPKetchum. I had a feeling you'd say that.



Wish they hadn't used that bottom stud for a bracket.

How hard is it to move out of the way once the nut is off?



What are the odds that things will shift enough to prevent getting either of the new studs back in?

Should i break/replace the first one, torque to 20lbs or so, then do the second one... or just pull both at same time???



The only evidence of the leak is a medium-size carbon spay toward the front... nothing on the back. Black gets to about the freeze plug. No obvious pieces of gasket sticking out but I can't tell if anything's missing either. I didn't "hear" anything until I recently installed and AFE intake so part or all of the hissing sound, as it relates to the leak, could be in my head. That turbo screech really got my attention. I don't want to suck a chunk of gasket into the turbo. Don't really want to hear that sound again either.



I'm idling w/E-brake right now...

Brake cycles every 5-10 minutes, maybe less frequently.

Coolant is about 160.

A little over 200 post turbo EGT.

Manifold is cool enough to touch briefly.

Should I do it warm, cold or somewhere in between?

Threadlocker (blue)... good, bad, optional on the stud threads???



So many simple questions... sorry.

It's not very cold outside right now. Actually fairly comfortable.

About ready to do something right now...

 

[HBarlow]

I'm no engineer or metallurgist but don't think the new and improved manifolds on the latest Gen III trucks are as likely to expand lengthwise and break off the studs on #1 or #6 like the earlier ones. I don't think you'll see any stretch at all.



My manifold was not stretched longer or warped at all. My leak was at #2. My friend's '05 leaked at #6. His bottom stud on #6 fell out in his hands when he attempted to remove it and the top one on #6 broke off in attempting to remove it. (Am I remembering this correctly?) His manifold was also badly warped at #6. I am no expert here but my impression is that his warpage and broken studs resulted from the long duration of the leak before he attempted repair. I caught my quickly and was on the way home when I began hearing it so I didn't continue running it leaking.



Thanks for the offer of a meal at FJ. I've eaten many of those coupon buffets myself.



I am on a "leave of absence" from transporting. I still have magnetic signs, transporter plate, and documentation but each day I'm home it seems a little less likely I'll return to full-time transporting.



I loved it up to three weeks ago and suddenly I was tired and not springing back quickly after a day or two off and was also vividly aware that I wasn't making much net profit anymore with fuel prices as they are.



Let us know how your repair works out.



Harvey

 

[PBrauer]

Minor update

Well, I was looking everything over one more time and now see that #1 is leaking as well. I didn't notice this one because the carbon stain is forward, going into the "dark", shaded spot. Guess I didn't shine the flashlight in there before. It's probably as bad, maybe worse than the #6 leak. There's a very small "stain" near one in the middle too.

Max boost is still normal... well past 35.



I guess that's a good enough excuse to wait and do them all. I'm still interested in any further advice. It's nice to know it shouldn't be too hard to do and I'm glad to have the heightened awareness of the studs... I definately want to replace at least 4, probably will replace all twelve.



I might be looking for a shop between Bangor, ME and South Bend,IN:

I-95 from Bangor to 495/395 around Boston.

I-84/81/80 across or I could take I-90.



I'd like to start a list of good, private shops along this route anyway.

I also need to find a Cummins dealer(s) along the same route. Hopefully the studs are cheaper there. Dealer got quite a bit for those first two and I need some other parts anyway. Dealers and shops are welcome to PM me. Town and shop phone are enough... I have GPS and will put everyone in there.

 

[Cattletrkr]

Do the job with the engine cold. I tried replacing my manifold when it was still warm/hot and I couldn't get the last two bolts out. Waited until the next morning and it was a snap. I reused all the bolts, no issues.

 

[PBrauer]

Do the job with the engine cold. I tried replacing my manifold when it was still warm/hot and I couldn't get the last two bolts out. Waited until the next morning and it was a snap. I reused all the bolts, no issues.

Thanks. Did you have leaks or were you upgrading (or both)?
I'd love to be talked out of another $100 worth of new studs...
Still leaning toward replacing the ends...

Edit:
I don't know why I thought I paid $10 apiece for the studs. $4. 52 x 5 plus $1. 72 x 7 for a full set at Cummins. On my way to get the rest.

 

[DPKetchum]

Doing the banana thing is the reason the ftermarket manifolds are three piece. Two cyls. on each section. Most all big rigs,tractors,indust. equipment is that way. Lots of inline engines I know of(gassers)seem to all warp the same way. Catch it soon and ought to be ok for a long time or if bolt holes line up ok pull the manifold and get a machine shop to deck it to make it level. Many ways to fix this. I'd do new end studs asap and if ok let it ride. Do it cold and retorque after a heat cycle or two. Make it fast and simple/cheap and see if ok first. Can always pull manifold at a later date if needed.

 

[Cattletrkr]

Thanks. Did you have leaks or were you upgrading (or both)?

Answer is here: https://www.turbodieselregister.com...003-2007/187145-cracked-exhaust-manifold.html

I never thought about replacing the studs/bolts but I didn't have any leaks out of the seals so I doubt I had any warpage that would have warranted the change.

 

[PBrauer]

Got it done...

Middle of the night under a light in a parking lot, but done.



Replaced all six gaskets. Most of them fell apart. #1 and #6 were the worst but from the looks of the gaskets they were all leaking. #1 studs weren't much more than finger tight. #2 studs were tighter than the rest. Plenty of PITA's but not really that bad.



Once the studs were all loose the manifold fell back exactly where I wanted it to... about 1/8" or so. Didn't have to pull on it and it didn't keep moving w/all studs loose. Basically sat there in a perfect position. Each one (gasket) came out easily but #6 stuck to the head just a little. I was still able to pop it loose with my fingers.



Spent about 5-10 minutes messing with that heater bracket then just hack sawed it off. Not worth the trouble... now or the next time. Used a single ended stud there (new). The tube is still solidly in place. Took me a while to realize there was another bracket below the stud. I'm not worried about it at all. Eliminated the hardest part of the whole job.



The old studs were probably fine but I did use the new ones. Block was still a little warm... around 30 degrees outside... probably 2hrs cool down before I started on the studs themselves. New ones went straight in.



There was some carbon "staining" on the head/manifold surfaces but no buildup. The manifold was sitting in too perfect a postition to justify trying to clean, although I would like to have cleaned #6 since the gasket did stick a little.



Hardest part was probably getting the retention strap off of the bottom of #5/6. I don't know it there's a trick to those things. I didn't replace them and don't know if I will. I will re-torque everything soon and probably start checking them from time to time after that.



I'm tempted to say that everyone should consider checking/re-torquing these studs... All of the gasket "layers" were in tact, no evidence that the manifold was pressing against the studs laterally, so low torque was probably the "root" cause of the leaks. No signs of cracks or warpage but all I could do was snoop around with a mirror/flashlight.



Jake brake at idle is much, much louder now. I'd forgotten how loud it was supposed to be. Idle is super smooth again... We'll see if my mileage comes back up. This might have been causing a lot of my problems.



Thanks to everyone for the help and info. I've needed to do this for a while now and it was the help in this thread that finally got me to get it started. It took me a few hours but this probably wouldn't take more than an hour or so with a helper.

 

[DPKetchum]

Nice write up. Glad there were no other issues for you.

 

[dpuckett]

... ... Each to his own but I tend to have more trust and confidence in the Cummins engineers who design, build, test, and market the engine and its many components than I do the aftermarket companies who sell parts for the Cummins engines. Cummins has a long public history of building million mile engines for the trucking industry. Their engines and components are not always perfect but I believe that they do their best to produce durable engines and components and also that they refine and improve components that prove less than durable.



Harvey

Keep in mind that stock is almost always a compromise between cost and performance. I agree, the engines are good, and last a long time, but as a percentage of the total, how many trucks make it to 3-400K mi in so short a time frame? Most problems can be blamed on age, etc.



Daniel