Quality OEM type motor mount replacements?

[Dragonslayer]

I'm thinking of fabbing a small aluminum heat shield that would somehow be attached to
the left side (stock) engine mount. I know that it won't protect the mount completely, but
I think it would help protect it from some of the direct radiant heat coming from the
exhaust manifold and maybe add a year or so of life to that mount (and thus maybe help
extend the life of the exhaust manifold by preventing cracks). Thoughts?

 

[McQue]

I like the way you are thinking. I think it's worth doing assuming you don't have other issues with a higher priority need, that will take a little time and effort.

 

[Talyn]

My 2000 already has a heat shield there. I wonder what year they started doing that. You can see it in this pic:

 

[Hellbent]

That's interesting. Don't think I've ever seen one of those.
None of mine have ever had a shield, but my newest xj was a '96.
I bet it started right about the time they got those precats.

 

[GrimmJeeper]

my 2000 CA emissions does not have that shield.

 

[Jonner]

I've noticed those heatshields on XJ builds that had the dual cats for newer emissions. Not sure if all of them use it or if its specific to certain years.

I have not taken apart most of my interior panels so everything is still pretty tight. If you've disassembled most of the interior a time or two, I could see how the panels and screws would loosen up and cause some rattling.

Have you thought about keeping the motor mounts and buying some thin adhesive backed felt? That should help the buzziness. That OEM motor mount on the one side sounds like a good solution too. You could offset the cost by selling the one Brown Dog motor mount on ebay or sell it to someone on Naxja.

 

[Talyn]

my 2000 CA emissions does not have that shield.

I've noticed those heatshields on XJ builds that had the dual cats for newer emissions. Not sure if all of them use it or if its specific to certain years.

I think that answers the question. Only on the cali emissions 00-01 models. I had thought it was more common, but it isn't something I typically look for.

I have not taken apart most of my interior panels so everything is still pretty tight. If you've disassembled most of the interior a time or two, I could see how the panels and screws would loosen up and cause some rattling.

Use friction tape where possible. Between panels and mounts and the like. When I took my dash apart to remove the HVAC box I used it where ever I could upon reassembly.

Since we are talking about heatshields I pulled a large one from a gas tank on a ford at the salvage yard. Its single layer but for $5 it was worth it. Its about 4' x 2' or so.

 

[Dragonslayer]

None of my XJs ('93, '98) have that shield. In fact, I've never heard of, or seen one of
those! Thanks for the photo. I'll probably use it to pattern a copy. How is it attached
to the mount?

 

[Talyn]

Two rivets on the inboard edge.

 

[Hellbent]

To answer the question about the vibes... My grille buzzed in the frame pretty loudly, something inside the dash on the passenger side "zzzzzzzz-ed" when cold. I could even feel the vibes in the steering wheel too. It made me feel like I was driving an old school bus, just too much to tolerate every day.
After swapping out the pass side mount back to a new stock one, the drive train still felt "solid" like it did with two urethane mounts, but almost all the buzzing and annoying vibes were gone.
Here shortly, I'm going to order the solid rubber insert BD mounts for the new xj and see how those do.

 

[HappyDog]

Too bad this thread didn't start a month ago -- it would have saved me some work. I had looked at the posts regarding replacement motor mounts and Brown Dog was universally applauded. There were a few posts regarding vibration issues, but they seemed to be limited to the poly mounts, so I ordered and installed the rubber ones.

Today, after 327 miles of use, I removed the Brown Dog rubber (not poly) motor mounts from my 1997 XJ and replaced them with OEM-style mounts. The BDs were just too harsh for me. I use the Jeep for going to interesting areas, which often involves dirt roads but not any really rough stuff. I like Saline Valley and Silver Canyon and am not much interested in bashing things to pieces like I would if I tried the Rubicon or Ershim-Dusy.

I'm glad you like the NAPA mounts (i manage a NAPA store in socal) but I hate to break it to you... just about all parts store mounts are made by a company called Anchor Mounts Inc.

I saw that Rock Auto had OEM-style mounts made by Anchor and by DEA Products. Not knowing which to order, I ordered one of each, figuring I would put whichever looked best on the driver's side, and the other on the passenger side.

The Anchor was made in Korea and looked best, so I installed it on the driver's side. However, the bushing isn't quite long enough so even with the through bolt tightened down to the specified 48 ft-lb, there is a 0.020" gap between the bushing and the ears of the bracket. That bothers me because it means the bushing can rattle on the bolt. I haven't driven it yet because the Jeep is in pieces in the driveway and it's raining now, so I don't know how much of an issue that will be.

The DEA was made in China and looked quite good, but after I put it in and dropped the motor down on it, that is when I discovered that they used a different thread pitch on the mounting stud. If they had included the matching nut, this would have been fine, but they did not so I had to jack up the engine again and put in the original OEM passenger side mount, which still looked OK.

I'm not enthusiastic about the Anchor because it doesn't fit tightly, and am even less so about the DEA because it requires non-OEM fasteners.

The Brown Dog motor mounts are well-made and I'm sure I would never break one. The after-purchase support is immediate. I followed all the directions about how to properly install them, and tightened the through bolts and then backed off so the washer could be spun. However the mounts don't do enough vibration damping for my tastes and use.

 

[HappyDog]

I know the buzziness can be annoying some times but I would argue to use a stiffer mount and I'll explain why.

Look at that giant space between the passenger side frame rail and driver side frame rail. The motor mounts connect the frame rails to the engine on both sides. After installing the stiffer motor mounts I noticed a significant improvement in turn-in steering feel and tightening of the steering/suspension up front.

All of this is true as long as the through-bolts are tightened to factory spec -- 48 ft-lb.

However, the current instructions from Brown Dog are to put a flat washer under the nut, tighten the through bolt, then back off just enough so the washer can be spun. They say this helps reduce vibration.

The consequence of this is that the two frame rails are no longer tightly constrained by the engine mounts.

Personally, I think it's poor engineering (but good cost-cutting) to use the engine and its mounts, which are supposedly for vibration isolation, to strengthen the frame. I support the idea of installing another crossmember between the rails at or near the trackbar mount.