I just found out why my truck is vibrating .
I went under and one of my motor mounts is junk.
Is it hard to change? What do I have to do?

Lift the motor with either a cherry picker or a jack (using a 2x6 to distribute the weight). Then, unbolt the old mount and bolt the new one back on.

Check Kennedydiesel.com for tips.

Lift the motor with either a cherry picker or a jack (using a 2x6 to distribute the weight). Then, unbolt the old mount and bolt the new one back on.


Is it 3 or 4 bolts?

Not sure on the 6.5. I haven't had to replace the mounts on my motor. Just get the mount, then you'll know. :)

on 4x4 it sucks it would be worth taking it to a shop, but the 2x4 probally wouldnt be to bad

where should I jack up the motor I thank the oil pan is not strong enought

Lift the motor with either a cherry picker or a jack (using a 2x6 to distribute the weight). Then, unbolt the old mount and bolt the new one back on.


you put the 2x6 between the jack and the oil pan

Is it 3 or 4 bolts?

It is 3. One tip is to use some tape around the middle of a universal joint for your ratchet. It will keep it in the angle you need until you get the socket on the bolt head.

I did mine when the engine was out, so I can't be of anymore help than that.

Use a GM OEM parts & change BOTH mounts,as you have to take the center bolt out of the opposite side to lift the engine. Avoid lifting by the oil pan !!!!

I wonder if i have bad motor mounts or a bad trans mount or all the above. My truck makes a THUMP when i step on the throttle while im moving, usually around 35mph or more and thumps again when i let off to coast. Seems to be worse the faster im going. Just looking at it it all looks fine. But i dont know.

I wonder if i have bad motor mounts or a bad trans mount or all the above. My truck makes a THUMP when i step on the throttle while im moving, usually around 35mph or more and thumps again when i let off to coast. Seems to be worse the faster im going. Just looking at it it all looks fine. But i dont know.

Could be a U-Joint or rear end slack. it happend to be a U-Joint on my 99. Just my .02 cents

Anythings possible, 236k on it and its never had ujoints or anything like that replaced. Wouldnt there be other signs if it was a ujoint? I do get a rough vibration while driving once in a while....only lasts for a split second then its gone again. Almost like something in the road but it isnt.

Anythings possible, 236k on it and its never had ujoints or anything like that replaced. Wouldnt there be other signs if it was a ujoint? I do get a rough vibration while driving once in a while....only lasts for a split second then its gone again. Almost like something in the road but it isnt.

Mine had a ruff vibration at take off (5 to 15 mph). then would smooth out. even though my 99 is a gasser it had about 225,000 miles on it as well when i replace them. Everyone i have talked to was always putting down the sealed U-Joints but that many miles on them is pretty good I think

I have to replace the drivers side mount....what a biotch!! One shop quoted me at least $700!!!!!

I don't know if I can do it myself in my driveway. Looks like I gotta drop my front diff, maybe more. Yikes!

Anyone care to walk me thru dropping my front diff??

I have to replace the drivers side mount....what a biotch!! One shop quoted me at least $700!!!!!

I don't know if I can do it myself in my driveway. Looks like I gotta drop my front diff, maybe more. Yikes!

Anyone care to walk me thru dropping my front diff??

I would not drop your diff, -it isn't necessary. I know many say to lift the engine by the pan, -but I would avoid that if at all possible, -lifting from the top is always better, -and nicer to your oil pan for sure.

Removing exhaust manifolds on both sides would be a big help and open up a lot of room to work. Remove the hood, round up a chain and a hoist, and lift it from the top side.

All in all, not an extremely fun job, but certainly not the worst job either. A second person is almost a necessity.

Plan at least a day in the driveway, -and that's if you have a good assortment of tools.

Ok so you're saying I can reach all the bolts if I remove the exhaust? So you mean lean over and reach down to remove the bolts?

How do I get to the bolt that is "behind" the mount(engine side, bottom going to frame)? Like if I was looking level at the mount from the front of the engine(thru the skidplate area) there are two bolts on the right of the mount and one on the left? Plus the center bolt? I think the two on the right would be easy, but I don't know how to get the the one on the left, between the mount and the motor.
Sounds a lot better than removing my diff

Ok so you're saying I can reach all the bolts if I remove the exhaust? So you mean lean over and reach down to remove the bolts?

How do I get to the bolt that is "behind" the mount(engine side, bottom going to frame)? Like if I was looking level at the mount from the front of the engine(thru the skidplate area) there are two bolts on the right of the mount and one on the left? Plus the center bolt? I think the two on the right would be easy, but I don't know how to get the the one on the left, between the mount and the motor.
Sounds a lot better than removing my diff

Well, removing the exhaust isn't absolutely necessary, -and would add a lot of time (particularly on the pass-side), -it just opens up more room. The plastic skid-pan in the front needs to come off, -and you will be able to poke your head up in there to see what you're dealing with.

The first thing that needs to happen is supporting the weight of the engine, then removing the center-pin bolts (one per side), -then lift the engine (BE CAREFUL NOT TO PINCH ANYTHING IN THE BELLHOUSING TUNNEL!) -for clearance for the frame-pad bolts (three per side). Sometimes they are stubborn little suckers, and will not separate from the ears (mini prybars come in real handy) Once separated, you will see the frame-pads are sort of shaped like a stair-step, -and have three bolts that bolt them to the frame member, -those are the tough ones that almost mandate a second set of hands. I did mine, -one guy in the front up behind the skid-pan area (looking toward the back of the truck), -and one guy underneath. With two guys, it ain't bad. Most of the frame-pad bolts you can do by yourself from the front (up behind the skid pan area), -a couple of others, -you will need another set of hands from the bottom side.

A couple of those bolts are a real mother to get to (being tucked inside the crossmember pocket). A swivel-head ratchet works good on a couple of them.

Once you get a look at the bolts from behind the skid-pan area, -you'll see it ain't too bad. I'd have a look it it with the skid-pan off, -you may find that removing the exhaust would only be a waste of time.

The only reason I mentioned removing the exhaust is because mine was off when I did mine, and it opened up a ton of room in there to see (particularly for the guy working from the bottom-side), -but I don't think it's absolutely necessary.

Removing the crossover pipe may be easier, -and give you the access you need?

Here's another tip for re-assembly. If you have a big hammer, -open up the ears on the engine-brackets a little to allow easier fitting of the new mounts, -OR, slightly grind the center member on the new mounts so that they are a slip-fit between the ears, -this makes life so much easier during assembly. If you grind the mounts, -don't "go to town" and get them too hot, -(for obvious reasons). It's just that sometimes new mounts don't fit between the ears worth a darn, -and can really add to the frustration when you're trying to get it all back together.

My .02

should I undo both mounts at the same time so the engine will go up easy?

should I undo both mounts at the same time so the engine will go up easy?

Yep.

you put the 2x6 between the jack and the oil pan

Avoid lifting by the oil pan !!!!


When replaced motor mounts on my Jeep YJ, I made a cradle out of a 4x4 and 2 sections of 2x4 so I could jack up the engine using the pan rails. Took all of 10 additional minutes and the materials were sitting around the garage.


Andy

should I undo both mounts at the same time so the engine will go up easy?

I just did my mounts. Asked the same questions you did. It is a pain. Took me and buddy 6hrs once we got started. Its really more about patients then anything. I thought I might have to drop the dif but once you jack the motor up it all seems to work out. I did one side at time. I thought keepng the other mount bolted up would help with alining the motor when it came to bolting up the new mount.

Its doable. If you have someone that will stick with you throught the whole project.

Rich