View Single Post
Old 03-09-2010, 12:51 AM   #1
Durallymax

Name: Durallymax
Title: Diesel Enthusiast
Status: Not Here
Join Date: Sep 2007
Member`s Gallery
Posts: 224
How To Remove LB7 Duramax

How to Remove your LB7 Duramax
So you need to pull your motor out eh? Either you blew it up or have a lot of go fast parts to put in it or both. Or maybe you are just curious as to what all is involved in removing one. Well this is a general guide to removing the LB7 Duramax motor. I will try to make this very thorough and explain every little detail like my other write ups. This guide may not necessarily be the same way everybody else does it, or the 100% correct way, but it is the way I do it and it works out well for me. This is off of the top of my head for the most part so some things may be missing or need some editing, I plan to update parts of it in the future as needed. BIG THANKS TO TOM (THEBAC) FOR THE PICTURES you will notice most of them are from him. Thanks a bunch man for taking time to do what I am always to lazy or in a hurry to do.
For starters some of you reading this may not think you will ever need to pull your motor. However I can say that if you plan to do something like a turbo swap and head studs at the same time, removing the engine will make things much easier and will give you less chances for things to go wrong, again just my opinion though.
Your probably wondering, do you need to be a full time mechanic? Not necessarily, I would say this is for people with moderate experience, but the biggest part is having some experience and knowledge and just being comfortable with removing your motor and realizing that hey, sometimes you’ll mess up but that’s how you learn and in the long run you are still saving money.
So what all is needed to remove it? If you have access to a car lift it will make things nice but it is not necessary. A cherry picker(engine hoist) is a must and you will want one that has a long reach and extends fairly high in the air, also make sure it can handle the weight of the Duramax about 1,100lbs assembled if i remember correctly. For the rest you will need basic hand tools mostly metric from 8mm-19mm. The only really special tool you will need are some fuel line disconnect tools, which are cheap and available everywhere.
Now let’s get started.
How To Do It
1. If you have a lift it I like to remove the transmission, to do this refer to my transmission removal guide. However if you prefer to leave the trans in the truck then remove the torque converter bolts before doing much else. To do this remove the starter by using a 15mm to remove the two mounting bolts and then just lay it out of the way then using a 15mm you can remove the bolts either with a small ratchet or a lot of extensions and a swivel on an impact. Have a friend line up each of the 6 bolts with the access hole by using a 24mm on the alternator nut and turning counterclockwise. However the correct way to do this is to turn the balancer bolt with a 36mm clockwise. Then towards the end of the removal procedure support the trans by the pan and unbolt the trans from the motor using a 13mm to remove the accessories which include the dipstick tube bracket (2 nuts on passenger side), transfer case vent tube(1 nut on top of trans) and the fuel line bracket (1 nut) on the drivers side. Then use a 15mm to remove the bolts. There are 9 of them. When finished support the transmission with a 2x4 across the torsion bars, this will be more secure than a bottle jack/floor jack and will leave your truck manuverable to free up the bay.
Click the image to open in full size.
Click the image to open in full size.
Click the image to open in full size.
2.Now that you will have the passenger side tire and fender liner out of the way, go to the drivers side and remove the wheel and fender liner on that side using a 22mm or 7/8" socket and body clip removal tools if you have them. There are wiring harnessess that fasten the to the fender liner so be sure to unhook them.
3.Now raise the hood into the service position. I suggest getting a helper, the hoods heavy. If you are tall like me you can hold it by hand and use your head to support it while installing the nuts and bolts. To do this first remove the ground wire running from the firewall to the hood using a 10mm then remove the bolts that connect the springs to the hood using 13mm tools and then flip the hood so that it is perpendicular to the floor, now you should be able to put the bolts through the service position holes in the hood and into the springs. And you now have plenty of room and light to work with, without removing the hood.
Click the image to open in full size.
4.Now you will want to disconnect the frontpipe if you haven’t already using an 11mm deep well. These are locknuts so an air ratchet will help save your hands.
Click the image to open in full size.
5.If you do not have your batteries disconnect yet, disconnect them using an 8mm wrench.
6.Now you want to remove your air intake tube by unplugging the MAF sensor, and loosening the two clamps on each end of the tube using a 7mm. NOTE: On 2002-2004 LB7s there will be an additional clamp which goes to the turbo resonator, this will need to be loosened as well. On stock setups the air box wont be in the way.
7.Now we want to drain the radiator, to do so there is a plug on the lower passenger side of the radiator that you can remove to drain it, it does not have a hex head or anything, just simple use a pliers to loosen it, it is not very tight. But prior to draining the radiator make sure that you have a way to channel the fluid into a container. I like to use the aluminum section of an old drivers side CAC tube I have laying around. But basically you need something to get the coolant to flow down instead of straight out. Once you get a way to channel the fluid, remove the cap from the overflow bottle to speed up the drain time. Reinstall the plug for now.
Click the image to open in full size.
Click the image to open in full size.

Front Clip Removal
1.Start by removing the radiator stack plastic cover by removing all of the body clips. This is the plastic piece that sits on top of the radiator stack/grille and has the belt routing diagrams on it. If you have a winter front you will have some screws to remove in lieu of some body clips.
2.Now you should have access to the one bolt and snap in tabs that hold the grille on. Remove the bolt using a 10mm, then compress the 4 green tabs that mount the grille to the headlight towers and pull them out. The grille is also fastened to the fenders on both sides. Remove the grille from these two points. You can get acess to these from inside the fender well. With these disconnect you should be able to finesse the grill assembly off. This is for GMC Grilles, Chevys may be different.
3.Now with that out of the way you can remove the 3 bolts holding the hood latch on using a 10mm. There is also a spot where the cable has a push in Christmas tree style holdown that you will want to yank out. Then swing the assembly to the side out of the way. NOTE: If you do not see where the bolts originally were, make marks, this is essential so that the hood latch lines up right upon reinstallation.
Click the image to open in full size.
4.Now you want to remove your headlight assemblys. Many should be familiar with this but if not, there are pins that hold the headlights in. On GMCs there are two vertical pins, simple rotate them 90* and pull them up. On Chevys there is on horizontal pin, again simple rotate this pin and pull it out. Then disconnect the harnesses from the light bulbs.
5.Now remove the marker lamp assemblys. To do this compress the push in tab on the outside of each assembly the swing it forward and out. Now remove the 3 bulbs in it and set the assembly aside.
6.Now you will want to remove the Headlight support towers. These are held on with a few bolts requiring a 10mm, and each side has 2 bolts requiring a torx bit. Remove both sides and set aside. Both sides are mirrors of each other, the pic below is the drivers side.
Click the image to open in full size.
7.Now you will have one wire left, it is the outside air temp sensor which is mounted on the radiator support A-Frame tower, disconeect the wire and the tabs that hold it to any part of the front clip along its path and swing it to the side out of the way.
Click the image to open in full size.
Click the image to open in full size.
8.Now your pretty much done but still need to remove the upper fan shroud. To do this you will first need to remove the TCM. To do this remove the two bolts that secure it to the radiator brace using a 10mm. Next simply unplug both of the connectors and set the TCM assembly aside. Now remove the 4 body clips that connect the two halves of the shroud, there are two on each side. Next pull the A/C line out of its mount on the passenger side of the upper fan shroud. Finally, remove the rest of the bolts that fasten the shroud to the radiator brace then remove the shroud and set aside.
Click the image to open in full size.
Click the image to open in full size.
Click the image to open in full size.
Click the image to open in full size.
  Reply With Quote