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 youíll mess up but thatís 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 letís get started.
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.
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.
4.Now you will want to disconnect the frontpipe if you havenít already using an 11mm deep well. These are locknuts so an air ratchet will help save your hands.
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.