I'm glad I got at least the front bushings replaced,the old ones felt like a sponge.The front seems tighter,although I still need to replace the upper front control arm bushings in order to take full advantage of my Jeep Cherokee intermediate steering shaft, new Bilstein front shocks and new bushings.I am going to use Larry's list as a guide for future body mount bushing replacment;
position----upper----lower
---1-------457915----348080
---2-------330986----457915
---3-------330951----377801
---4-------330951----457915
---5-------556755----none
---6-------348080----377801
---7------1242754----457915
As they are somewhat expensive,I think I'll just do 1 or 2 over the next few years.I might plan on doing the rear ones next.
Guy

you can get energy suspension, washers, all mounts for 140$ i believe US. i put them in my car and made a big difference the old mounts were all torn and worn and the bolts were broke on a couple of them.

Hey Clint,I priced the poly bushings,but I have decided that the approach I want to take is to have poly for the suspension bushings,but OEM rubber for the body mounts.Dont ask why,just got it in my head that this is how I want to do it.It might have something to do with MAP's suggestion to go with firmer bushings at the ends and softer in the middle.
Guy

yeah makes sense man, its up to you!. I just put my last bushing in today. Although i never drove the car with the old bushings it should ride nice and tight now, good luck with yours. nationals in a few weeks!!

Oh yeah,it's gonna be nice to get to Moncton.Ive got my fingers crossed that I'll be able to get my control arm bushings done before we go.We've got a couple of camping trips planned,so time is somewhat limited.
Guy

Made a mistake on the bolt listing on page 3. Here is an update

Adding bolt information to this post

The bolts are:
Position 3 = M10x1.5x55 - grade 10.9 GM part unknown
Positions 2, 4-7 M10x1.5x80 - grade 10.9 - GM part 12337833
Position 1 = M10x1.5X95 - grade 9.8 (grade 10.9 will work)

From looking at the chart I think the washers are .515X1.56X.19. Had to squint and my shop manual does not show the sizes like the chart from above.

Dealership, NAPA or hardware store can get you the right bolts. Make sure they are the right hardness. I actually found these bolts by the pound at Shoppers (a Hardware Hank affiliate).

GMpartsdirect show 12337833 can be had for 1.20 each plus shipping.

Dixies has full set of bolts and washers for $70. Kirban has the bolts only for $28.

I'm looking for a set of Delrin bushings for the core support. If anyone has any or knows where to find them, i would appreciate the help.

Generally have to buy a set. Could post on SS parts wanted.

Is it possible for someone to make and sell me a set of bushings for the number 1 and number 7 location? Sorry but this is all gibberish to me.

Do you want new or used?

Do you want something close to stock or do you want harder bushings?

It is easier to get stock type bushings in ones and twos

looking for something stiffer and better than OEM bushings for those two locations.

I don't know where you can buy one at a time poly bushings. Summitracing has full sets for as little as $100. You might be able to buy a set and split it with someone. Also, you might track the manufacturer down and see if they sell them in a set of 8 for positions 1 and 7. Summitracing.com and Jeggs have them.

Perhaps you can You can manufacture your own. I think some people use hockey pucks.

Map says Delrin block work well. They are probably as expensive as buying a whole set of poly bushings, but are better. They scraps pieces are available on EBAY.

MAP is quite the expert and has posted the following about replacing the core support bushings. Similar process would happen at the rear.

"The dimensions for the Delrin blocks are: bottom half of bushing: 1.0" x 2.5" x 4.0". For the top half, they are: 0.5" x 2.5" x 4.0". The long dimension of each bushing half gets aligned with the long dimension of the radiator support; i.e., the long dimension goes transverse to the car.

The bottom half of the bushing "sits" on a fender washer of approximately 2.0" OD, 0.5" ID, and a thickness of about 0.10" (this dimension isn't well confirmed, but it corresponds to the height required to allow the bushing to "sit flat" on the stepped frame contour at this location, which in turn corresponds to the wall thickness of the frame.) The fender washer surmounts the fastener used to clamp the bushing with the frame and radiator support.

The top half of the bushing receives another fender washer, or perhaps two, of the same dimensions under the bushing-clamping fastener head.

I didn't check, and I don't well recall, but the inside of the frame where the fastener protrudes, possibly receives a washer as well under the hex nut that goes with the machine screw that clamps the bushing assembly together. As for the machine screw itself, I seem to remember using 1/2" UNC grade 8, with a length of 3". It's absolutely imperative to use a split-ring lock washer under the hex nut, since Delrin does exhibit some creep, and we don't want that assembly to come loose over time. [N.B. 1/12/09: the use of a prevailing-torque nut in this location would also be a good idea. Again, you don't want to take any chance that this assembly will work itself loose.] Using a medium-strength threadlocker as well couldn't hurt, but never omit that lockwasher. [N.B. And/or the prevailing-torque nut.]

As for the clearance hole in each bushing half to receive the fastener, it should be located on the centerline of the long dimension of each bushing half, and about 1.0" to 1.2" (not well confirmed) from the end of the bushing which is nearest the outboard side of the frame."

HTH,
MAP

Hope it helps

http://shop.ebay.com/i.html?_nkw=body+bushings&_armrs=1&_from=&_ipg=

http://cgi.ebay.com/ebaymotors/Energy-Su...sQ5fAccessories

Try HERE!

Good post

Update on the bolt information

The bolts are:
Position 3 = M10x1.5x55 - grade 10.9 GM part 14085301
Positions 2, 4-7 M10x1.5x80 - grade 10.9 - GM part 12337833
Position 1 = M10x1.5X95 - grade 9.8 (grade 10.9 will work)- GM part 10049638

From looking at the chart I think the washers are .515X1.56X.19. Had to squint and my shop manual does not show the sizes like the chart from above.

Dealership, NAPA or hardware store can get you the right bolts. Make sure they are the right hardness. I actually found these bolts by the pound at Shoppers (a Hardware Hank affiliate).

GMpartsdirect show 12337833 can be had for .78 each, 14085301 for 2.60 each (pack of 5 min), 10049638 for 2.52 each plus shipping (25.84+shipping). List price for each is 1.33, 4.37, and 4.25 respectively so for $30.54 plus tax you could buy for less locally.

Dixies has full set of bolts and washers for $70. Kirban has the bolts only for $28--however they list the bolts as 8.8 strength.

where in the GM service manual does it discuss or show anything about the body mounts? I have a hard time finding anything in mine. I would at least like to know how they are numbered. Thanks!

Look in the FRAME and BUMPER section of the factory service manual, should be 2A if you have a Helm's.
Bob

Look back on page 4 of this thread, you'll see a couple of scans I put in from an 88 service manual.

got underneath my car today and bushings were as follows

Pos # || Upper || Lower
1 || 457941 || 1403780
2 || 10005267 || 457915
3 || 330951 || 377801
4 || 330951 || 457941
5 || 488610 || ----
6 || 14032559 || 377801
7 || 14032560 || 377801

I also have a couple laying around..

457915
457941 (x2)
377801 (x2)
1225795 (x2)

Any suggestions on swapping the ones I have laying around??? Also can any of these go in the #5 Position??

Thanks in advance

1225795 is the original upper for 87/88. These are hard to find. If you don't want them I might be interested. It was coupled with 348080 (still available from GM).

I think your position 1 lower is the upper, the upper is the lower according to documentation in prior pages.

Position 5 is an oddly shaped mount. It just sits in there. I bought the Buick 556755 (still available through GM), but it is softer than the original 488610. My 488610 looks like it is in really good shape so I am tempted to use it again.

Here is a prior post of mine that talks about options for using various bushings:

Well, it has been a while, but here is the result of my research and what I plan to do:

Many G bodies had bushings left out. Some that are left out (position 5) make the rider softer. I would think that leaving out lowers and only using washers would make the rider a little harder.

As I understand it, the Grand Prix bushings were the genearlly stiffer than the MC. They are as follows:

position-----Upper----lower
--2---------330986----457915
--3---------348080----457941
--4---------348080----457917
--5---------556755----none
--6---------330942----377801
--7---------1242754---457915

I could not find all of the MC bushings. In position 1 I could not find the 1255795. It is very similar to 457915. However, 457915 is a little harder and more shallow on the first inside shoulder. I know some other people are going with 377801, which is shorter and a little softer than 457915. I think that going with a harder substance that fits tightly with 348080 may make the responsiveness of the cornering a bit better. I also put stiffer mounts on position 7. Staying away from delrin might protect my A-pillars. I have a t-tops.

I could not find MC uppers for positions 1, 2, 5, 6, and 7. The lowers from softer to harder are: 457941, 377801, 457915. I have been told that 457915 will work for position 1 upper and all lowers 2-7.

Where I could not get MC parts, I went with the Grand Prix parts. In some of the positions, I stiffened the lower part a bit since I have a little more HP and wanted it a bit firmer ride. Since GM had a pattern of having positions 3 and 6 lowers a bit softer, and since I had the parts, I went a little softer there.

Here are my choices:

position----upper----lower
---1-------457915----348080
---2-------330986----457915
---3-------330951----377801
---4-------330951----457915
---5-------556755----none
---6-------348080----377801
---7------1242754----457915

I believe all the parts I chose are all still available. GMpartsdirect.com, oepartsource.com, discountpartshub.com are all potential sources. I would note that you will quickly find Dixie's price a decent one IF you have to order in ones and twos and pay shipping from each source. Try and bunch up your order as much as possible.

Hope this helps.

Larry

Thanks Larry, im not sure if I will be using the 1255795's or not. .I have the steel cup like Guy has in my 86 with a 1403780 sitting it in at a 457941 on top. .I will try to take some pics of it today to give a little bit clearer picture. . I am thinking about replacing the 457941's in Pos #1 with the 1255795's as it looks like it would be a little tighter fit and the bushings seem stiffer than the 457941's. .sorry if this confused anyone. .i will try to take some pics after i charge the battery

pic of the lower bushing and steel cup



The pic on the left is the 1403780 lower bushing mated with the 1255795 on top

The pic on the right is the 1403780 lower bushing with the 457941 on top. .

Looks like the 1255795 would provide a little tighter and somewhat firmer mount.

Any comments?? Thanks

In our 88 we did not have the cup like you guys do. Just a combo of the two bushings and some washers.

hmm..i wonder what reasoning was behind the decision not to use the cups in the 87 & 88's.