Are solid motor and tranny mounts a good idea or a bad one? I'm not concerned with any vibrations. Do any of you run solid mounts?

I run one solid motor mount on the left side only. It works very well.

Originally posted by Paul Gagnon
Are solid motor and tranny mounts a good idea or a bad one? I'm not concerned with any vibrations. Do any of you run solid mounts?

as in no rubber bushing

I wouldn't run solid mounts due to breakage problems with engine block and frame.

I think you mean poly bushing motor and tranny mounts? That's what I run...work great so far...waaaay less motor and trans movement...haven't tried it much on the trail yet but should work great!

Should help with the old dual t-case motion on the rocks, but does transmit LOTS of drivetrain noise to the cab. Don't know if I'd do it ina DD>

You should try a bushing style mount, or use chain to limit some of the movment.:)

Originally posted by Nate C
I wouldn't run solid mounts due to breakage problems with engine block and frame.



That is a concern but is this a hypothetical problem or have you seen it happen?

I
I think you mean poly bushing motor and tranny mounts?

No I mean solid as in a piece of steel with the appropriate holes drilled into it so you can bolt it up. That's why I said solid. Thank you for assuming that I don't know what I am asking.

thank you for being a biatch...

If you want to do it, the best way I have seen is engine plates. They mount motors in drag cars that way.
It does transmit alot of vibration and noise though.

Do you guys have any picture of these poly bushing mounts.

Check http://www.mountainoffroad.com - their Bombproof are pretty sweet. I know it's not your applicaiton, but you could definately get some ideas.

Paul, it depends on your application; I wouldn't try it with a Toy four-cylinder, they have a tendency to shake a lot. With most smallblocks, it wouldn't worry me. Actual solid motor mounts may not be a great idea on a trail rig, 'cause of frame flex--the frame flexing (and the motor/tranny not) could ultimately rip the mounts off the frame.

Bottom line, it'd work well on some stuff, but not everything. If you need a bombproof Toyota motor mount, we've got it; if it's bombproof smallblock stuff you're looking for, there's a lot of racecar companies out there that have it.

http://www.rockstomper.com/images/products/drivetrain/motormounts/mount02.jpg

http://community.webshots.com/storage/1/v0/1/29/34/28512934OzzVKqXkQU_ph

Jeeper

My application is a 3.8L on an F350 frame. Doubt there is anything off the shelf that would work but at the same time I don't know if it is possible to damage this frame that way.

Originally posted by Paul Gagnon
My application is a 3.8L on an F350 frame. Doubt there is anything off the shelf that would work but at the same time I don't know if it is possible to damage this frame that way.

Unless you're stiffening the F350 frame in ways Ford never imagined, don't do it. The frame is too flexy. Jeeper's example is a fairly easy thing to build, I've done mounts like that on a buncha custom swaps before, and it's stout, but it's not bolt-on. The mount I posted is a bolt-on Toyota four-popper mount, simple stock replacement. Since you're swapping, I'd say, break out the welder and copy Jeeper's pic. Jeep YJ spring bushings work well for that kind of setup, just make a plate to fit the block on each side, a couple tabs off of it, and a tube to hold the bushing, to the frame. Then set the engine where you want it and go to town with the welder. But solid mounts (IMHO) in a trail vehicle aren't a great thing.

Correct me if I'm wrong,,,(which I'm sure you would anyway :flipoff2: ), but hard mounting an engine without some sort of rubber bushing to absorb the vibrations and hard knocks in my opinion would not only transmit all engine drivetrain noise directly into the cab, but would also shorten the life of your engine by transmitting those same vibrations, knocks, and bumps directly to your engine components.....thus causing premature component failure...right?

What I'm using.....
Jay

http://www.mindspring.com/~jayk3/bbspics/motormounts.jpg

Paul I wouldn't mount it solid, not in a trail rig. As everyone has said there's to much flex in the chassis for this. Worrks good for the car guys, but not for us.

Take alook at the prior post. Those mounts are rather easy to fab up. Even if the 3.8 has a wierd mount on the block, i.e. big block MOPAR, where the tabs are cast into the block you can still make this system work it's just a bit tougher. Start with the factory motor mounts, cut away everything but the actual metal piece(s) that bolt to the block the start building from there. Pretty simple really once the motors is hanging on the shop crane between the frame rails.

Most anything that needs solid mounts wont last long anyway, but the right way to do it, is first have a very stiff chassie, then make moter plates for the front then between the motor and trans then between the trans and transfer case all will be good, and you will fill every time the motor fires a plug.:D

Originally posted by kerryphillips
hard mounting an engine would not only transmit all engine drivetrain noise directly into the cab, but would also shorten the life of your engine by transmitting those same vibrations, knocks, and bumps directly to your engine components.....thus causing premature component failure

Transmitting all that vibration to the cab will cause premature minor-component failure in some cases. CD players come to mind... light bulbs, switches, relays, etc., other electrical stuff, all doesn't much like vibration.

Transmitting road vibration (trail shock?) to your engine, probably is of minimal consequence; the vibration of the engine itself is enough to make just about any road vibration or trail shock (shy of, say, a head-on crash) pretty minor by comparison.

I've got a few friends who have solidly mounted their motors and I'm going to solidly mount mine. Flex isn't as big a concern with a rollcage tied into the frame at multiple locations....

As far as vibrations, have any of you ridden in a Jeep with solidly mounted drivetrain? It isn't really noticeable, you'd be surprised.

CJ

Paul,
You're welcome, if you want specific answers, ask specific questions!

"Actual solid motor mounts may not be a great idea on a trail rig, 'cause of frame flex--the frame flexing (and the motor/tranny not) could ultimately rip the mounts off the frame. " Or crack the block, and yes I've seen this.

I'm running something similiar to Jay's, except that mine weld in to the original steel mount on the motor and then bolt to the original yota frame mount.

BTW, I'm sure that a Jeep with a soft top would be much better, due to a lack of a hard roof to transmit the vibrations.

Solid is O.K, but you have to have a bushing at the tranny, there is a certain amount of flex that the tranny (auto) needs to have
ericfilar@fatcity

I'm runn'n a TBI in my YJ, T18 and 20. After busting a brand new OEM left side mount smashing new air cleaner and tearing up my electrical, I said fok that. Got myself some cheapo Moroso solids. They work just fine. Over a year with no problems, however I did keep poly's on the tranny and tcase... :D

I used the poly bushing type like everyone else and it worked awsome in my 4runner. It rattled my teeth but never broke.

SCOTT, check you pirate message i sent about the motor mounts i got from you last weekend. thanx greg

Thanks for all the info guys. I forgot to figure in frame flex. Any other opinions?

So far there are two camps:
- Poly bushings on engine and transmission
- Solid mounts on engine with poly bushing on tranny.

I wouldn't solid mount one and not the other go poly bushings on both. Your motor will thank you.

It's either, or...I have no problem with solid mounts, especially if you have gone the full tie-in cage and are trying to make the whole package as strong as possible. But to mount the engine solid and the trans/tcase in rubber/poly is just asking for trouble. The engine and trans. are bolted together, and are cast materials, if one end can move and the other can't something will give.... I have a wheeling bud who used a solid mount for his trans. and used standard motor mts. on the engine... yep the TH400 split like a walnut. If you are going to go for it, don't half step. Vibration won't be a problem and huge shock load won't be a problem as long as everything moves together.

I know the drag car I worked on had solid mounts. It had a 2'x4' aluminum plate bolted to the front of the motor. I'm not sure about the tranny as I was working on welding up custom headers.

HTH

Originally posted by Pook
I wouldn't solid mount one and not the other go poly bushings on both. Your motor will thank you.

why? i had 2 poly mounts on my 22RE. when i drove it, it sounded as though i was inside a speaker box, that had a blown speaker(=loud vibes). i replaced one of the poly mounts with the stocker and its alot better. most of us are driving FORWARD, and lets say you rev. your engine and then let out the clutch. the driveline creates torque causing the driver side mount to experience tensile stresses, and the passenger gets the compressive. i think the rubber mount on the compression side will noticebly damp some of these vibes. toyota mounts(two metal plates with rubber sandwiched between) seem to only get destroyed on the tension side because it stretches the plates until the rubber is seperated from one of the plates. so, a poly mount would be helpful here. Think of it like a hinge on 1 side, so most of the vibration is transmitted to the rubber mount on the other side. .....thats my take on it atleast.
:zzz: