Write-Up: Filled Rear Motor/Transmission Mount

even if you dont have a WhippledRiv i'm sure the OE prices for the front and rear trans mounts (under the rack and near the rad) have you wondering if anything better can be done?!?

well i figured it out, i found inserts that work and cutting the rubber out of yer old mount halps make it even stiffer...i have to upload the pics of the rear mount but these pics should get the idea across...
as soon as they go into the Riv i'll have two cores to rework if anyone else is looking for a cheaper option than OE/poss future urethane mounts.

YES!!! I HEART YOU

used a non GM insert, got the good mounts for 12$ each plus steel for shimming the new inserts with steel shims and tack welding them to the insert and housing. (not shown in this pic)

you can see how i cut up the OE mount and wedged all the additional rubber into the mount.


since we have the 4t80e that the Riv's getting we figured we'd at least try these out for how much the whipple could twist the old mounts lol
these shouldnt rattle the riv with the IS4 cam etc but they sure as hell wont move under load like the OE's did!

i have more pics but i havent uploaded em yet...the rear mount is a work of art lol

I could use the rear mount. I fouled my spare when I tried to cast it with polyurethane. I did cast the passenger mount and the front mount... came out verey well. I have no idea how to do the driverside mount in poly. Rear mount should be easy now I have the process down. I'll post some photos and info in a different thread... didn't mean to hijack yours!

no problem man, i just wanted to show others that you can use a cleap early chrysler mount, make it work quite well. these are temporary solutions for us since we have no clue how she's gonna feel with the IS4, and since eric still drives clients around we cant have it too harsh. but if he doesnt mind the much stiffer rubber mounts we will be making the solid motorplate type mounts.
i've got a recomendation fer your poly mounts.
if your looking for voids for some movement take MCd's straws and burn the ends closed to length and just insert them around the the through bolt after pouring in 75% of the urethane, the side will still be solid but with the internal voids it might make things better fer ya

Agreed... I think both setups will work as intended. I use my car to drive clients around as well but after evereything I intend to do, I might have to look for a 2nd "company" car. Last month I had the Pres and VP of the company I am contracted to, in my car for several days while we were at a trade show. I imagine they would have preferred a rental car but..oh well. We got lots of looks downtown ATL. I will trade you a passenger side mount core (everything intact) for your rear mount core- dont need the rubber insert just the mount bracket.... did you ever find a home for your orig fuel logs?

ewolfe0050 wrote:

Agreed... I think both setups will work as intended. I use my car to drive clients around as well but after evereything I intend to do, I might have to look for a 2nd "company" car. Last month I had the Pres and VP of the company I am contracted to, in my car for several days while we were at a trade show. I imagine they would have preferred a rental car but..oh well. We got lots of looks downtown ATL. I will trade you a passenger side mount core (everything intact) for your rear mount core- dont need the rubber insert just the mount bracket.... did you ever find a home for your orig fuel logs?

we wont be using the P side mount the car is getting a urethane sleeve mount using a modifed W body block bracket (to clear the external sump pan fittings/remote filter adaptor plate) the rear mounts comming off the car soon (prob by the middle of the week or so) so the new ones can go in (ground both mounts/cleaned them up, looks very nice with fresh black paint!)
no havent sold them i havent really tried hard though...since we are using alot of the -6an stuff for the two fogger fuel solenoids, we are selling just the rails and end fittings for a plumb your own setup if someone's running an aftermarket adj fpr... you still want em? 200$ and we'll throw the mount in

Negative on the rails... went with PRJ's for a couple different reasons. How much for the rear mount? and I'd like to see a photo of your rear mount setup before you install it if possible. Also, where is hangover park IL? I have some business in Peoria within the next week or so and wouldn't mind taking a look at your whipple setup and picking up the mount if we can agree on price.

lol hanover park 60133 i dont think peoria is near me lol i'll talk with eric later tonight on the mount

Did you find out what you want for the mount? Need it asap otherwise, i'm going to have to go thru Ed next week... got to get a PS bracket for a '00 Bonne too for the Mezeire WP clearance.

write-up:
https://rivperformance.editboard.com/series-ii-engine-transmission-f4/write-up-rear-motor-transmission-mount-t6797-30.htm#113123

hi i need a rear motor mount, but does anyone know who stocks these and how much?

There is another write up on here somewhere regarding the mounts. All of them are mentioned with P/N's IIRC.
I didn't know any better at the time and paid GM retail a few years ago for the rear and front mounts at $300.00 each when I had my Trans rebuilt.
At the time they were not available in the aftermarket. That may have changed by now, I don't know.

The rear mount for the '95 is a good bit higher than for the '99, I know that for a fact! I got an aftermarket one for the '99 for $35 and when I checked a few months later on one for the '95 it was right at $100
I'm not sure of part numbers or availability but I do know they "were" higher.

I would gladly have paid either $35.00 or $100.00.
If you find the source, please let us know.

I just found one site that has them for $110 with free shipping. Ill try to dig that name up when I go back. The GM dealership said $335. I laughed at them.

Well, zzperformance has poly motor mounts for $60, a factory replacement set for the same. Problem is, one of them is for W-body cars only. They seem to specialize in Grand Prix stuff and it doesnt say anything about Rivieras. Does anyone know if these cars all took the same motor mounts?

KillaKeninaRiv wrote:

Well, zzperformance has poly motor mounts for $60, a factory replacement set for the same. Problem is, one of them is for W-body cars only. They seem to specialize in Grand Prix stuff and it doesnt say anything about Rivieras. Does anyone know if these cars all took the same motor mounts?

Definitely not.

I figured they would be interchangeable. What cars are interchangeable with the Rivieras? I noticed last year I tried putting a caliper from a Grand Prix on the old Riviera I had and it didnt fit either.

KillaKeninaRiv wrote:

I figured they would be interchangeable. What cars are interchangeable with the Rivieras? I noticed last year I tried putting a caliper from a Grand Prix on the old Riviera I had and it didnt fit either.

Many of the other large GMs - The G- platform includes the Park Ave too. The Caddy STS is the G- platform but a different engine and transmission, so they probably don't use the same motor mounts. I think the Olds ninety-eight might have been. The aurora didn't get the 3800, so I don't think it has the same mounts either. They seem pretty exclusive to Rivieras, and maybe Park Avenues if you are lucky.

Yeah and zzperformance said they were W-Body mounts. I figured we might have the same body but apparently not. Wouldve been nice to have mounts readily available for $60! Time to hit the junkyard and pray I guess lol

Where was it that you saw a rear mount for sale around $100.00 New.????

I would get one of those before I went looking at the junk yard. Unless of course you find a low mile Riv in the boneyard.

I just went to the auto parts store a few hours ago and they told me that GM was raping me lol. There are four mounts, one on the passenger, and three on the transmission on the drivers side, front driver, center, and rear driver. I think it was the rear driver that was bad. He said they had them for $80. Sounds like a winner.

KillaKeninaRiv wrote:

I just went to the auto parts store a few hours ago and they told me that GM was raping me lol. There are four mounts, one on the passenger, and three on the transmission on the drivers side, front driver, center, and rear driver. I think it was the rear driver that was bad. He said they had them for $80. Sounds like a winner.

What Auto Parts Store?
And if you know, who mfg the mounts.

I found the mount earlier today at Autozone. It was a rear transmission mount manufactured by DEA, and it cost $108 after tax. It turned out I didnt need the mount. Apparently when the previous owner swapped drivetrains, they left out the bolt from the trans mount. The new one had 40k miles on it, but it felt like shit running because of that mount. I found the bolt for $1 at Suburban Nut and Bolt and in 20 minutes, it was like new.

KillaKeninaRiv wrote:

I found the mount earlier today at Autozone. It was a rear transmission mount manufactured by DEA, and it cost $108 after tax. It turned out I didnt need the mount. Apparently when the previous owner swapped drivetrains, they left out the bolt from the trans mount. The new one had 40k miles on it, but it felt like shit running because of that mount. I found the bolt for $1 at Suburban Nut and Bolt and in 20 minutes, it was like new.

Figures.

Great catch.

Albertj