school me on body lift and motor mount lifts....

[mike4089]

the body lift i understand why and ill be purchasing the jks 1.25 body lift very soon....what i dont under stand is the 1 inch motor mount lift that they recommend to go with it...what does this do?? and is it neccessary

[Rocky529]

When you raise your body 1", your radiator shroud will raise with the body and hit the fan. The body lift comes with re-location brackets, but the 1" MML will raise your motor 1" also to match the height of your body. It is really just an excuse to install a 1" MML which will ultimately help your rear driveline angle and reduce/eliminate any vibes you may have present as a result of a suspension lift. It also helps with the angles of your t-case linkage after a body lift is installed too.

[joemomma4040]

Can I install just a motor mount lift to eliminate minor driveline vibes that are left after a suspension lift and tc drop

[grogie]

Originally Posted by Rocky529

When you raise your body 1", your radiator shroud will raise with the body and hit the fan. The body lift comes with re-location brackets, but the 1" MML will raise your motor 1" also to match the height of your body. It is really just an excuse to install a 1" MML which will ultimately help your rear driveline angle and reduce/eliminate any vibes you may have present as a result of a suspension lift. It also helps with the angles of your t-case linkage after a body lift is installed too.

Rocky, I just went over to 4x4 Xplorer.com and read the instructions on a MML. Looks like a bit of work! Were you getting vibes with your D44 and lift? Plus off topic, but how is your lift working out? Is that the 2.25" BB from 4 Wheel Customs? Plus did your rear axle move any with the lift? I have heard it probably will and would need a new rear track bar to correct. Thanks, as your setup is pretty much what I have in mind.

[Brown Dog]

A MML should never be installed just because you are installing a BL. If you have no vibration problems now, you could change the angle of the driveline to a degree that you would create vibration. You can relocate the fan shroud to accomodate the BL.

Go here and read the section on vibration. There are also a couple of links that talk about driveline angle.

http://www.browndogindustries.com/index.asp?PageAction=Custom&ID=5

[Rocky529]

Originally Posted by grogie

Rocky, I just went over to 4x4 Xplorer.com and read the instructions on a MML. Looks like a bit of work! Were you getting vibes with your D44 and lift? Plus off topic, but how is your lift working out? Is that the 2.25" BB from 4 Wheel Customs? Plus did your rear axle move any with the lift? I have heard it probably will and would need a new rear track bar to correct. Thanks, as your setup is pretty much what I have in mind.

It's not that much work, I recommend you install it. I don't know if i would have any vibes or not because I had the MML installed before installing my 2.25" lift. For what it's worth, I had a 1.75" lift without a MML prior to changing to my current set-up and I had no vibes. You can install your suspension lift and body lift without the MML and see if you get vibes. You can always add on the MML later or just simply drop your t-case a bit to eliminate vibes.

Yes, my rear axle shifted to the passenger side and my front axle shifted to the driver's side... normal with any suspension lift and the way to correct that, as you mentioned, is to install adjustable track bars. I didn't because with only a 2.25" lift, the offset is barely noticeable... I don't see it and I'm pretty anal about those things.

And yes, 4 Wheel Customs with OME shocks.

[CHRRRIS]

I have a 3" SL, and I had installed a 1" TC drop along with it... I want to get rid of the TC drop...

Right now I have no vibes, but like I said, I want to get rid of the TC drop, would I be able to get rid of it with just a MML? Or should I do BL and MML?

I don't want any vibes after w/e it is I do, so hrmm...

[Rocky529]

Originally Posted by CHRRRIS

I have a 3" SL, and I had installed a 1" TC drop along with it... I want to get rid of the TC drop...

Right now I have no vibes, but like I said, I want to get rid of the TC drop, would I be able to get rid of it with just a MML? Or should I do BL and MML?

I don't want any vibes after w/e it is I do, so hrmm...

BL does not affect driveline at all.. you can install a 10" BL and still be vibration free. The MML may or may not cure your vibes.. but it will definitely help and allow you to lessen the amount of your t-case drop to maybe .5" or .25"... or remove it altogether. Every Jeep is different.

[Incadude]

Originally Posted by Brown Dog

A MML should never be installed just because you are installing a BL. If you have no vibration problems now, you could change the angle of the driveline to a degree that you would create vibration. You can relocate the fan shroud to accomodate the BL.

Go here and read the section on vibration. There are also a couple of links that talk about driveline angle.

http://www.browndogindustries.com/index.asp?PageAction=Custom&ID=5

Thanks Man! That is the exact answer I've been looking for in the past few months. Right now my driveline is finely tuned by my local 4x4 Dr., and I do not want to change it at all. But, I do want a BL in the near future.

Thanks again....

[Jeepinty]

Just a side note, I had the poly motor mount lifts on my TJ with an auto for about a week before I couldn't stand the motor vibes any more. The polyurethane motor mounts transfer engine vibrations better than the stock rubber isolators and when I was a stop light the whole jeep would shake like a heroin addict.

I would recommend using a MM spacer that uses the stock mount such as this one LINKhttp://www.4x4rockshop.com/scripts/prodView.asp?idProduct=9579 or a MM that uses rubber mounts.

I am sure someone will fly in to defent polyurethane MM's but this is my experiece with them.

[ps3tv]

Originally Posted by Jeepinty

I am sure someone will fly in to defent polyurethane MM's but this is my experiece with them.

Ok, I'm going to fly in here, but not to defend polyurethane motor mounts. They were on my Jeep when I bought it, and I have been tolerating the motor vibration for almost two years now. Thanks for the link for the motor mount spacers. I don't want to change my driveline angle because the driveline is smooth as silk now. But the motor vibration at idle drives me nuts. I'm going to have to buy new stock motor mounts because they didn't come with my Jeep, but it will be worth it.

ps3tv

[CHRRRIS]

Originally Posted by Rocky529

BL does not affect driveline at all.. you can install a 10" BL and still be vibration free. The MML may or may not cure your vibes.. but it will definitely help and allow you to lessen the amount of your t-case drop to maybe .5" or .25"... or remove it altogether. Every Jeep is different.

Right now I have no vibes. If I add a 1" MML/BMML and get rid of my 1" TC drop, is there a possibility I could obtain vibes? It sounds right in theory that if I raise the driveline 1" and then raise the TC 1" I should be where I am now... right? or wrong..? lol I want to get rid of these damn TC spacers!!!

[Jerry Bransford]

When I installed my first set of motor mount lifts made by Currie, they were made from polyurethane which caused a noticeable increase in engine vibration to be transmitted into the cab. When one of them broke due to a weld failure (I wish I had known how to weld back then), I replaced them with rubber torsion "Bombproof" motor mounts from M.O.R.E. (Mountain Off-Road Enterprises) and the vibes went away.

Whenever I can, I use rubber mounts because they last MUCH longer than many think they do, usually until after the vehicle becomes a resident of a junkyard. Which is one reason I don't like polyurethane body lifts, they are made from polyurethane which just transmits more vibes and is more expensive than need be. Those who make polyurethane body lifts try their best to convince everyone rubber mounts are no good or that they start going bad within just a few years at most. Nothing could be further from the truth.

[Rocky529]

Originally Posted by CHRRRIS

Right now I have no vibes. If I add a 1" MML/BMML and get rid of my 1" TC drop, is there a possibility I could obtain vibes? It sounds right in theory that if I raise the driveline 1" and then raise the TC 1" I should be where I am now... right? or wrong..? lol I want to get rid of these damn TC spacers!!!

Yes, there is a possibility that the 1" MML won't allow you to completely remove your t-case drop, but worst case scenario is it will allow you to lessen the amount of t-case that you have. You can do this with washers rather than 1" spacers.

[Jeepinty]

Originally Posted by ps3tv

Ok, I'm going to fly in here, but not to defend polyurethane motor mounts. They were on my Jeep when I bought it, and I have been tolerating the motor vibration for almost two years now. Thanks for the link for the motor mount spacers. I don't want to change my driveline angle because the driveline is smooth as silk now. But the motor vibration at idle drives me nuts. I'm going to have to buy new stock motor mounts because they didn't come with my Jeep, but it will be worth it.

ps3tv

Same crap with mine, I cannot stand engine vibes. Try the MORE mounts that Jerry has, they are lift mounts with stock type rubber isolators.