Diagnosis and Repair of Your Imperial Motor Mounts

Imperial Home Page -> Repair -> Engine -> Motor Mounts

Tip from Philippe about the 1957 models:


Be careful with 57 motor mounts ! There was TWO motor mounts: the first type was used on early 57 Chrysler & Imperial until an undetermined date (June 1957 ?). At this date and on 58 models, there was an improved motor mounts, designed to "more thoroughly absorb normal engine torque impulses". The 1st and 2nd insulators are not interchangeable ! If you want to put the 2nd (or the 1st) you must have the correct brackets ! It's easy to know if you have the early or the last mounts: the early type bracket have an "open" top and the insulator stud is centered, the second type bracket have a "closed" top and the insulator stud is off-centered. Be careful if you order insulators ! 

This information is shown on Mopar parts Information General bulletin # 236 (12/24/57). Parts numbers: early model: insulators # 1827 448 (2), brackets # 1735 008 & 009. 2nd model: insulators 1828 247 (2) (but on my car insulators I've seen 1828 246 ..), brackets 1828 262 & 263. In every case, brackets are specific to Imperial models. According to the Canadian Parts list, the early type is used up to CE57 29123 but on my wrecked 4dr 57 Crown (C57 22828) there was 2nd type yet.

 Tip from Bob (choices in fixing bad motor mounts):

1. Make sure you know what kind of mounts you need. The big mounts for Imperials (from ?? to '66, see the '66 service manual, page 9-5) are not available in any parts store. 

2. Your choices are NOS (too expensive), used mounts, rebuilding the mounts (need cores and costs about $160) or fabricating a replacement. Pros & cons for each choice.

 3. I've tried two sets of used mounts and had bad luck with quick failures. I've also worked with some friends on fabricating a "permanent" replacement, using the original mounts with modern mounts as an insert. We did this without a car as a reference and made some wrong choices, so the first try did not work. I'd be glad to share my ideas on a project like this so we can come up with a long term solution for this problem that will be with us forever! 

4. Rebuilding (Revulcanization) of old motor mounts has been reported as offered by Bob's Barn in Redding, CA (see IML web page). I called this place and he thought these could be done for about $80/each. You must provide a "core", which I now have. Has anyone used this service? More ideas?

Reply from John:

I had my mounts ('65) revulcanized when I had my engine rebuilt. I got them done at Then & Now Automotive in Massachusetts (617-335-8860). It cost about $160 including shipping. It took about 3 weeks. All I can say is that after a year they haven't failed. The revulcanizer has to have a mold for each different mount; if they have the mold, they can rebuild them forever. I was told in no uncertain terms that NOS mounts are a waste of time & money. The material is 30+ years old so it's very doubtful they'd last long, and they are way too expensive.

Reply from Jim:

Steele Rubber (advertises in Hemmings) rebuilds motor mounts and they are a FIRST CLASS outfit. Might give them a try.

Question from Tom (354):

I have noticed several posts regarding motor mounts and it made me wonder if I should be changing mine. The car isn't road worthy yet so I can't comment on performance, but it seems to me that now is a good time to change them while the front end is off the car. I guess I have two questions: 

1 - How can I tell if they should be replaced? 

2 - How do I go about replacing them? (special tools etc.)

Reply from Kne:

If the mounts are still in one piece, and are not obviously cracked or damaged they should be o.k. On the other hand, if the car is apart and the motor is out, and you can find some new ones at a reasonable price, it would be an easy time to replace them as preventative maintenance. Old ones will make great spares twenty years from now when they may be harder to find. I always run a torque-chain from the drivers side of my engines to the frame, with a turnbuckle in the middle, and adjust it so there is a small amount of slack. This will take a load off the motor mounts and generally keep everything else attached to the motor from moving around and flexing too much.

Question from Asa (354):

Can someone look under the hood of their '56 354 and tell me if the motor mounts go in front of the engine bosses or behind?

Reply from George:

I looked at my '55, the mounts are behind the engine boss castings on both sides.

Question from Bobby (413):

I need a referral for a hard-to-find motor mount, specifically a 1965 driver's side motor mount for a '65 New Yorker 413. I had the old one strapped together but the rubber is now completely shredded. So far, the only place that has stated that they can get one will need 5 days and $200.00 for the part. That seems like a long time and a lot of money. IMPERIAL CONTENT- this car will be out of commission until I can get this part SO, I will be required to drive my Imperial that much more on these unseasonably hot days until the New Yorker is back in the rotation. Can anyone give me a reputable referral on this part?

Reply from Darrell:

Did you try Mitchell Motor Parts in Ohio or Andy Bernbaum in MA. Both advertise in Hemmings. A cheaper alternative would be to go to a Chrysler dealer who has been around for a long time and have him do a parts search for you. If you have the part number it would be easier. My guess is that it is a fairly common part.

Question from Paul (413):

I have a 1962 Imperial and I need to replace the engine mounts. Can anyone tell me the official part number so I can tell my mechanic?

Reply from Chris:

The parts numbers are: 2128 572 - right, 2128 571 - left.

But you might have trouble finding them. If so, check the IML Parts section for "Imperial Services". Steve Charette is making new ones, using Dodge truck insulators and different looking brackets. I have a set and they appear to function exactly like the originals, but have a different appearance.

Question from John (413):

 I need to replace the front motor mounts on my '62 LeBaron. I'd like to do it without hoisting the engine. It looks like I ought to be able to jack up the engine on each side an inch or so with a bottle jack. While the engine is supported one side at a time with the jack, I can R&R the motor mount (1 bolt at the frame, 2 at the engine). Has anyone tried this trick or something similar with success?


From Mark:

I have a '63 and did mine with a floor jack. Just jack with a wooden block on the flat place between the engine and tranny. Remember to loosen the nuts BEFORE jacking.  Also, take the tranny mount loose before you raise it. I didn't do it in an hour; but, hey, it's a hobby not a race. Very easy job. Especially compared to pulling a starter!

From Bob:

I had one motor mount for my '66 (should be nearly the same as yours) replaced by Julius at "Restorations by Julius" and watched him do it while chatting with him. I seem to recall it was a relatively easy 30 minute job on a hoist. Some of the bolts were loosened from above before it went up and Julius used along screw post of some type to raise the engine slightly - if I remember right - to get the old mount out and slip the new one in. I just checked the service ticket for the job - it was for one hour of labor to change the mount and do an oil change.

From Steve:

I once accomplished the task when in a pinch by using a bottle jack with a 2x4 resting against an oil pan rail. Just be sure you have the engine shored up in case it slips.

From Kerry:

Don't know if it's like my 73 but the 73 was a real bit-h!. Fan hits the shroud, power steering hose too short, can't get to the bolts. It can be done but it probably took me 6 hours and I had it up and down on the lift dozens of times. 

Question from (413):

I need some help locating motor mounts for my 1966 LeBaron. My local mechanics have exhausted the local area suppliers. Are '66 mounts supposed to be this hard to get? 


From Chris:

Go to:


Great quality stuff. Get the trans mount while you are at it.

Follow-up question from Tim:

Are motor mounts what the imperial services folks call floating power replacement mounts? Just want to be sure before I buy.

Reply from Chris:

Yes, there are two kinds of Floating Power mounts that are offered. The economy style, which are adaptations of Dodge Ram engine mounts, and the original style.

The original style ones were not yet in production when I needed a set, so I used the economy ones. They fit perfectly and were easy to install. My only comment is that the Dodge Truck rubber is a little softer than the original Imperial mount, which allows a little more engine movement than I would like. But this goes unnoticed behind the wheel.

Steve Charette told me the original-style mounts use a different durometer(?) rubber and would be exactly like original equipment. Steve is a retired Ford engineer (but big Mopar fan) whose products are of highest quality.

I would not hesitate to order anything from him.

From Paul:

Do not mess with rebuilding or repairing old mounts. The only way to go on this is new, and it looke like imperial services.net is a great resource.

These mounts are susceptible to fracture and can lead to other trouble.

From John:

I had my motor mounts rebuilt years ago by Antique Auto Cellar in Weymouth, Mass. and they're fine.


I've also purchased the transmission mount from Imperial Services and that's also fine!

Either way is good.

From Marc:

Try this site, I used this guy for my mounts. http://members.aol.com/damperdoc

First rebuilt set failed, so he took them back and did them again, at no charge. First batch had contaminated rubber, so fell apart soon after installation.

Second set has worked fine for 4 years now.

Question from Norm (413):

Does it make any sense to wrap the motor mounts in some kind of strong line( fishing line) many times so as to assist the mounts and provide a back-stop, so to speak, beyond which the mounts will not flex. I ask this because I remember that in the mid 60's, GM issued a Tech Bulletin advising the creation of a turnbuckle loop between the upper control arm and the exhaust manifold on the driver's side for Chevy's and Buicks-both of which were notorious for breaking mounts in 65 66.. This helped prevent the engine from lifting if the mount was broken-which they frequently were. I realize this is a different approach than the one I am asking about, but it tells me that some kind of outside support system is useful. Has anybody tried the fishing line or anything like it to prolong mount life??


From Bob:

Sounds like you are describing a "torque strap lite".  The disadvantage of this approach in an Imperial is the "solid" metal transmits vibration to the rest of the car - very un-Imperial. Your "fishing line" concept probably would not do this, but I wonder how long it would last under the heat & stress? The best long-term approach is adapters - made by Steve Charette, Tony Vickers & Don Savard. If you build an adapter around a more common motor mount, replacements will be easy almost forever. Probably will cost a point or two at the next concours... Steve's contact information is:

Steve Charette 

Imperial Services 

P.O. Box 802 

Mount Morris, MI 




From Kerry:


Unless you were going to have a show car, I'd be VERY tempted to adapt a more available motor mount to your 413/440. It should not be too difficult and only the purest of purists would probably ever know and then only if they really looked hard. Those suckers are really buried under all the other stuff.

Question from Rob (413):

Well, despite asking many times about the condition of my mounts to every mechanic, they gave up the ghost recently. Luckily, I got away with only the fan clutch mildly denting the radiator; could've been much worse.

So, anyone know where a good set of mounts can be had, or do I need to pull them and have them rebuilt (which will be a bear; I can't drive the car to a garage, and she won't fit in my garage with the hood up!)?

In other news, I'm fully restoring a '50 DeSoto Suburban. Huge car, but very simple. Really makes me appreciate how sophisticated the Imperial is. Unfortunately, now I want to take the Imperial down to the frame too, and do a full restoration on her. And then the '66 Newport. And then I'm done (until I buy another car)


From Jeff:

Tom Hannaford at antique auto parts cellar can rebuild these "floating power" motor mounts. His number is 781-335-1579. He is rebuilding some 65 Imperial motor mounts for a friend of mine for $145.00/pair. I think that the motor mounts may be the same for 1959-1965 Imperial, but I'm not certain. He does very nice work and I have had great luck with everything that he has done for me. You may be able to call Bob Hoffmeister, Lowell Howe, or Murray Park and buy some used ones... send them to Tom Hannaford and then install them on your car.

From Bob:

You can get an emergency repair by having the mounts "pinned" - a place in Burbank put bolts through both of mine & I still have one in place 3-4 years later - getting close to finishing up my adapter project. I may very soon also have spare cores which can be rebuilt.

Question from Jay (413):

I've got a problem with a persistent rattle in our '62 Crown. I am wondering if anybody has had a similar problem and if so, what might it be? The rattle seems to be related to the transmission. It started with Reverse gear, a kind of heavy thumping rattle that I could feel in the floorboard whenever the transmission was in Reverse. I inspected around the rear of the engine and top of the tranny and nothing appears to be loose that might cause this rattle. A few weeks ago I noticed that the rattle has progressed into the realm of the tranny being in Neutral. Not as prevalent in Reverse now, the rattle was more obvious in Neutral and sometimes in Drive under specific throttle/load conditions. I looked for anything under and around the transmission that could be causing this. I did find that the two lines that run from the tranny back and fourth from the trans cooler did come rather close to each other - close enough to possibly cause a rattle if vibrated. I took some bailing wire and wired them together where they cross in hopes of stopping the noise. This did not work. No longer in Reverse, the rattle has now settled into the forward gears. On the freeway I can still hear and feel it over the road & wind noise. It is so annoying that I have been shifting into Neutral whenever I am stopped at a traffic light. Has anybody ever heard of such a thing before? Could this be an internal transmission noise? I have checked the ATF level, engine warm in Neutral and the level is fine. Any ideas on what to check?


From Bill:

Would it be possible that your tranny mount is bad? Or maybe the u-joints? It could be internal but not likely the way you described it. This is one of those things that always happens to me. I wish there was a way to ride under the car while someone else drives. Really though, you could safely out in the boonies, have someone else drive while you open the passenger door and see if you can detect where it may be coming from. Hold on or have your belt on. Don't want you to fall out. I have heard that a mechanics stethoscope can help pin point noises also. Never have tried it though

From Bob:

This sounds a little like what I experienced when my motor mounts started going bad - the fan was hitting the shroud very lightly as the engine shifted around, first in reverse and sometimes right after starting. With the engine off, turn the fan by hand to see if any of the blades are touching the shroud.

Follow-up from Jay:

I will have the mounts checked out by my semi-trusty transmission shop. With the front wheels blocked by a step-up concrete curb in the carport, I am able to leave the car running in Drive while I step out and look for the noise. I have tried to locate the noise this way with not much success. from outside the car, it sounds like the noise is coming from the firewall area, but who knows. With the engine at idle and the fan blowing like crazy it's harder to hear the rattle from outside the car rather than inside.

Reply from Elroy:

To check for a broken motor mount, it's not that difficult (but really requires two trustworthy people) Park the car in a area like against the curb where it will have difficulty moving. Set parking brake firmly. Place one person inside the car. Have them put one foot firmly on the brake and keep it there. Raise hood. Stand at either front fender. not in front. Have the person inside shift car to drive and depress accelerator about 1/3.Make sure they keep foot firmly on service brake. If the motor mount is fine, the engine will rise up dramatically- could be to one side, maybe not depending on how many mounts are bad.

Reply from Dan:

Don't take me wrong, but you guys are being waaaay too careful with this. Just raise the hood, get in the car and start it. Put the car in gear and, looking between the cowl and hood, tap the gas about 1/3 or so and watch. If the left side of the engine jumps up about 2 feet and looks like it's about to bounce out...you've got a bad motor mount. If the back of it jumps up and you hear a loud *SMACK* then you need a new transmission mount.

Question from Roy (440):

I have broken a motor mount on my '72 Imperial.  Question: what year and make motor mounts will work on my vehicle?


From Bob:

This is a semi-informed response - I've only researched the motor mounts for '66 and older. You should have a MUCH easier time to find a motor mount for you '72. When I went to NAPA and other parts stores for my '66, there was a lot of part number misinformation, but mounts for '67 and later cars should be listed and I would expect to be more correct. If you can actually see your mount to get a rough idea of its size and shape, all the better. Then go to a good parts store, ask for the part by year & model and check it to see if it looks like the one on your car. There are several companies that should make motor mounts for these "later" Imperials and a good parts persony/book should come up with cross-referenced numbers.

From Pete:

You should be able to pickup mounts at most auto parts stores. If not, Spring 'n' Things has them for about $10 each (800-903-9019). If you want indestructible mounts, I suggest Schumacher mounts. Don't have the number, but I picked up ONE (driver's side) at Chryslers at Carlisle for $45. MUCH stronger than stock. It has a kind of torque strap built-in.

Question from Jack (440):

Anybody else have any problems with motormounts on their '73? The aftermarket ones my trusted mechanics used have broken 2 times. They wondered if I could find a better source.

Reply from Joe:

I put new ones from Napa on my '72. The only reason they broke soon after putting them on was that I was hot-dogging it doing burnouts; no shame when you put the torque to them. The set after that was Napa again and no problems what-so-ever.

Question from Pete (440):

I'm going to be installing new engine and motor mounts come springtime on my '73 Imperial. Reason: Driveline vibration at 80+mph. I've got new (balanced) tires, 4 new u-joints, and changed the rear end fluid. Mounts are now suspect. I've heard that the "parts-store" brand don't last. What would be the best ones to get and where can they be had? 


From Joe:

Having driven and made many repairs on a 73 New Yorker which is very similar as to engine and transmission mounts, the reason the engine mounts do not last is due to the design of the mount assembly. It is placed directly under a spot on the valve cover which will drip any leaking oil from a bad valve cover gasket onto the rubber of the mount. With passage of time and heat and cold exposure, the rubber will disintegrate. It might be possible to fabricate some sort of aluminum drip shield to cover the rubber of the engine mount and prevent this from happening. The OEM and after market replacement engine mounts are of equivalent quality, but, neither will hold up to a continuing exposure to dripping engine oil. It would be best to replace the valve cover gaskets and use the rubber high-temperature gasket type before replacing the engine mounts. Also, be sure to check your fan blade to be sure it has not been bent by hitting the fan shroud. Remove the fan blade and lay on a flat surface. The fan should not rock back and forth. A bent fan should never be straightened, but, should always be replaced. The type of steel they are made from becomes brittle and can fracture and send a blade flying at high RPM. I heard of one mechanic who was killed by a blade which broke off like this. So above all, BE CAREFUL!!

From Mark:

had that done a couple of years ago to my '73 and I'm glad I did. I was swaying all around in there. I remembered a '72 sitting in an old boy's junkyard and pulled a set. They were good, so my mechanic stuck them in there. It helped a lot but I still get some vibration when I get up in that speed range. I think the U's are OK but I'll ask the mechanic about the rear fluid. When I got the car, I had a hard time finding an idler arm to replace the cracked one...and that cut down on the cha-cha and the car wandering off to the right. I know how you feel because I start to lose confidence in the car when I open her up like that, especially passing trucks on steep inclines. Front end balls/rods good, shocks are good, control is good, alignment/tires good. This Y-body suspension can be a bear, but when it's "on" it's incomparable. I never even thought about finding a new set of mounts because I knew where a donor car was. Thanks for bringing up the rear fluid angle. I never thought of that.

This page last updated July 14, 2004.  Send us your feedback, and come join the Imperial Mailing List - Online Car Club