Replacing DD15 Rear Engine Mounts, What to Remove?

I have plans on eventually replacing the rear engine mounts on my DD15. Do I need to drop the driveline? What about the transmission? I cannot find any official instructions from Detroit on how to replace the rear engine mounts.

Initially I thought the transmission needed to be removed to take off the engine mount bolts, but I can confirm that there is space (a little) to remove the bolts. What I haven’t tested is if I can torque the bolts, although I should be able to torque most bolts. I’m thinking I may need a small socket to perhaps make the torque wrench fit on all bolts/nuts.

 

Engine mounts are a product of the truck manufacture not the engine. What are you working on?

 

Just because something has a torque spec doesn't mean every darn thing needs torqued. Especially something like engine mount bolts. Just get them good and tight. I own a couple torque wrenches but really only break them out for internal engine work.

Just my opinion and it's worth just that, nothing. Do what helps you sleep at night

 

I have plans on replacing the rear engine mounts myself, but I want to make sure it can be done without dropping the driveline or transmission. I don’t want to jack up the engine and damage my driveline or something else.

 

I guess you can say I’m a little too crazy about torquing everything. Hahaha. I’m learning that not everything needs torquing. Even Detroit workshop manuals don’t have a torque spec for everything. When they leave it out, I either just give it a good tight or I guess the torque and make notes to myself for future use.

 

Most all rear engine mounts can be replaced without removing the transmission. Someone on this forum told me otherwise, I did not argue.
The one on the left side of a Ford with a 3306 was especially difficult.
Do not let the engine roll or move toward the mount that is removed. Tighten the bolts back like they came loose.

 

You can google a bolt torque chart by size, thread and grade. If you find a more advanced chart it will have more variations for shoulder bolts, bolts in aluminum, different types of washers, dry or lubricated. Is anti seize a lubricant?

 

I’m still learning how to read bolt sizes and grades. Once I get the hang of it, and I can begin using those charts. I’ve known about that method for finding torque specs, but I still find it complicated to understand. Then as you mentioned, there are different torque specs for dry or lubricated threads. Personally, anti-seize is a type of lubricant.

ProjectFarm YouTuber recently tested out various anti-seize lubricants and it turns out that plain motor oil can function as an anti-seize, although it won’t beat anti-seize lubricants.

 

I did not know Freightliner had workshop manuals. I’ve been trying to access the DTNA Connect site, and I think finally I’ll be granted permission to access it. It looks like they may have some workshop manuals!

 

I changed mine on a 12.7, first time didn’t drop driveshaft. Should have dropped oil pan, and jacked it up, safely. Could hoist it from the top, with proper equipment. However you do it, be safe. I almost lost the tip off a finger.