That XJwonders tranny mount looks solid. I was gona ask if there are any decent tranny mounts. I’m on my second anchor mount and it’s already going out after a week. Junk. I know mopar makes an offset mount, but I couldn’t find a centered mopar mount for my 2000. Any other good mounts that would be recommended?

 

Napa drivetech mounts have been good to me

 

I got poly on my last brown dog mm, LOVED it. To be completely honest I didn't notice much in the way of excess vibrations. Might try rubber this time, but erm won't poly last longer? But yes, here's another vote for brown dog, never again going with another company for MM!

 

I'm not entirely sure "solid" is what you want.

I did a lot of reading on this on various automotive message boards before pairing an OEM style transmission mount with hard rubber motor mounts, and what I found was a lot of conflicting information. Some say you need a hard transmission mount to reduce the amount of power lost to into the chassis. Some say you need a softer transmission mount to allow the tail of the transmission to move a little if the body flexes. Some say that if you upgrade to hard motor mounts, you must also upgrade to a hard transmission mount, although I still haven't been able to make sense of that reasoning. Others say that if you use a poly motor mount or transmission mount, the other end needs to be rubber, because there needs to be a soft point in the triangle to prevent excess stress on the drive train.

So I ended up just thinking it through for myself. I reasoned that if I have upgraded motor mounts that limit how much the motor can move, I should have a weak point in the triangle to allow for body flex. If you look at how the OEM-style mount is constructed, there's a lot of rubber there for strength and durability, but it's molded to allow movement in all axes to reduce stress on the transmission housing. I figure that if I put a hard mount back there with hard motor mounts, body flex and vibration are going to put ridiculous amounts of stress where the transmission mates to the engine and risk cracking the bell housing.

I look at these aftermarket transmission mounts with bushings instead and can't help but see problems. First, they're designed not to let the tail of the transmission move at all, which just seems like they're begging for damage to the bell housing or transmission case, especially when you take one of these Jeeps off pavement. Second, the weight of the drive train is sitting on the lower half of that bushing, so at most you're supporting it with half an inch of material. Contrast that with the OEM-style mount, with has several inches of rubber supporting it at angles for strength while still being soft enough to allow for some flex. Even the much harder Daystar mount still has a big chunk of poly there for extra support.

I could very well be wrong. But these hinge-style poly transmission mounts are still relatively new, and I have a suspicion that in the next few years we're going to start seeing both cracked bell housings and bushing failure as more people buy them. To me it seems like a lot of the people buying them are just jumping on a fad and not really thinking through whether they're the best choice.

Describe "going out."

 

As in its garbage out of the box. Causes tons of vibrations. There was a nice writeup on here about a year ago describing how the anchor mount is bad. If i remember correctly, one of the things was that the rubber was too soft and the mount collapses under weight. This causes the exhaust to come into contact with the crossmemebr. I got rid of my anchor mount a week after putting it in.

 

The anchor mount are garbage. My stock mount with 170k on it sagged less than the anchor replacement.

I went to Rock Auto and they told me to just keep the mount and apologized for the crappy quality. The anchor one sagged so much the exhaust would hit the trans crossmember which seems to be a common issue.

I have a set StinkyFab motor and trans mounts waiting to go into my XJ. They use a proprietary poly that is only a few durometer points firmer than rubber. All the welds are top notch, it's zinc coated, and the price was good for the motor + trans mount kit.
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​​​Might try to install those this weekend, I'll report back if I do

 

Not sure how you're getting that the brown dogs (and similar) have more material than OEM. The material is more evenly distributed because it uses a round bushing, but it's certainly not MORE material. And you definitely feel the vibration of the motor more.





In all reality, there's probably more material in the OEM mount.

But you don't buy Brown Dogs or any similar mount because it has MORE rubber in it. You buy it because it's more durable and it keeps the motor and drivetrain in place better. Same with the round-bushing style transmission mount. Look at any race application or custom-built tube buggy. They're not using OEM anvil-style transmission mounts, they're using round bushings because they're much easier to replace, they keep the transmission in place better, they're more durable, and they're easier to install into a custom application than the OEM stuff.

Don't get me wrong, if you prefer the OEM stuff, that's all well and good... just don't get the wrong impression about the aftermarket designs.

 

Been following this and there is an important factor when it comes to motor mounts. The weak spot that wears and breaks faster is on the torque "lift" side, the side that pushes "down" gets a lot less abuse and lasts twice as long. So when looking at the bushing type compared to an OEM replacement, there really is not much more material on the OEM than in the bushing type "on top" of the bolt sleeve to counter act against this lifting action.

 

Meh. I'll concede that point. The aftermarket mounts are still better supported in the three directions other than straight down.

I'm not sure that last sentence is always true. Motor and transmission mounts in general are intended to allow some movement. Otherwise we'd just have hard steel welded mounts that would shake the car apart. We install the BD mounts to reduce the amount of movement allowed because the stock mounts are not up to the more rigorous conditions we put these vehicles in.

Once you have the BD motor mounts, however, the motor isn't going anywhere regardless of what you put under the transmission. So at that point a hard transmission mount seems unnecessary except in the most extreme situations like jumping dunes at race speed. At slower speed flexing that puts high stress on the unibody, or just for regular street driving, I think a hard rear mount would be a bad idea. It's not just unnecessary, but it also transmits stress to the transmission housing that the OEM style mount was partially intended to alleviate in the first place.

I could be wrong. I'm just explaining why I went the way I did.

Is that true? With ours, wouldn't you still have to remove the mount just like the OEM mount and reinstall it just like a replacement OEM mount? Then you'd have the extra step of driving out the old bushing and pressing in the new one. That's not all that complicated, but it wouldn't be "much easier to replace" than a stock mount you just toss and replace as a unit.

 

One thing I know is that there are two known notorious design issues with Chrysler engineering they decided to never address. One is over kill on engine mount material causing premature failure, and the second is weak frame strength where the steering box is attached. Pretty much on everything they made...

 

Which way did you go? OEM or OEM replacement?

The difficulty I'm having is finding an OEM-style trans mount that at a decent price. I tend to agree with your thoughts on the trans mount, but XJWonders and Stinkyfab mounts sure seem to be at a better price/performance ratio.

 

What I like about my mounts is the fact it's easier/ cheaper to replace the bushings instead of the whole unit. For example, 2000-2001 transmission mounts are centered. A replacement unit would be $75

A pair of bushing halves cost approximately 5 dollars

Only takes 10 minutes to replace them on the bench.

I put my mounts through rigorous testing with hours of highway driving along with rockcrawling trips. I haven't noticed any problems so far. Sure it vibrates the jeep more over the OEM style but I preferred that.

To be honest. I put in the motor mounts first with the OEM trans mount &I drove it. Then I put in my trans mount. I didn't notice ANY difference in vibration. I think it felt slightly more secure.

Now with the supposedly thinner material that make up the "wall" around the sleeve as opposed as to the thick rubber chunks on the motor mounts. I don't think there's any problems with that considering they use the same bushings in the many control arms and boy, I have seen people abuse their 4,000 lbs rigs. Jumping over obstacles, pounding the axles on the rocks, hurling a couple of tons of steel across terrain and those control arm bushings still survived.

The motor weigh only few hundred. Sure there's torque involved, but i think it's only minimal.

I'm not saying you are wrong though. I see what you are saying and I understand your reasoning behind it. From your experience, it worked for you. That's what's important.

 

Todays secret words is...'serviceable'.

 

This.

 

Yep... ^^^ this...