Body mount bushing differences

[SUX2BU99]

I just bought a set of Energy Suspension body mount bushings for an 81-up and as I took off the passenger front cab bushing, I see that my new ones are fairly different then the one I removed. I don't see how the new one can go onto the body support that I have. I may have the frame from an 80-down but I dont' know.

The old bushing has cone-shaped lower donut that goes below the support. The bolt is long and passes through this lower donut, through a round role in the support, through another donut (cylindrical) that has a sleeve in it, and then up into the support where it threads in. The hole in the support is just big enough to pass the metal sleeve through, which the bolt passes thru.

The new bushing has a lower and upper piece. The lower is slightly cone shaped but has a rather large metal sleeve embedded into it. In the center of this bushing is a slotted hole, not a round hole. When trying to put this onto the support, it doesn't seem to fit right. The sleeve diameter is much bigger than the hole in the body support. It seems that the upper and lower bushings are to fit onto each other but that doesn't seem possible with my body support. Does it sound like I need 80-down bushings? Anybody got pics?

[SUX2BU99]

I guess I've answered my own question.

Here are the bushings I have. Apparently I have a 73-80 frame:


And these are the ones I bought, and subsequently have to return:


Apparently my cab is an 81, but my frame is not. Is there a VIN stamped on the frame somewhere??

[86 chevy silverado]

I would think if you had the '81+ body, you would use the newer bushings as well, its been a while since I personally have had a pre '81 truck so I'm not positive.
The vin might be found on the drivers front frame rail on earlier trucks (I've been told) but have never located the vin on my '81 2wd or either of my '86 4wd trucks and all has been down to bare frame except for the cab. I have never been hellbent to find them either.

[HAULIN IT]

Sux, I'm unfamiliar with the aftermarket parts, however there are a couple things that I'm thinking. The top picture looks like a slightly modified (molded a little different) 4wd set. The tall "Michelin man" ones are the back (upper) mounts. The ones in the second picture are nothing resembling what I've seen on a GM truck. A couple things to concider... The lower half, other than holding the body from lifting up in a turn, ect. have no effect on body placement or panel fitment so the A/M company may have made them a different shape than the original (read...they may have something else that uses the same size hole so they put it it the set). On the 2wd trucks all Six top bushings are the same & all Six lower bushings are the same. The GM part numbers cross between the '70's & into the '80's. At this point, my own opinion from your pictures, you still don't have a 2wd body mount set for an '80's GM 2wd truck. If anyone feels this is not correct, please speak up. Good Luck, Lorne

[SUX2BU99]

Thanks guys. It's been difficult finding the exact pics for my application from websites. I do know that the bushings on my truck now look like the ones in the top pic, BUT I have only taken out one bushing so far (front pass side of cab) and it looked like the top pic: cone shaped lower and short cylindrical upper donuts. I know Energy Suspension does list two different part numbers for 80-down and 81-up bushings. I also know there's no way I can use both 1/2's of the bushings I bought on the body supports I have. What the lower pic does not show is how those bushings come apart. There's a lower and an upper that pull apart. The lower has a metal sleeve in it that the upper slides on to. I could use just the upper on my truck and not the lower, but I wouldn't feel right not having the right application on my truck.

Another question, when lifting the body to get at these things, is it okay to put a 2x4 on the floor jack and then jack against the rocker? My tank seems to be in the way to conveniently get to the rear body mounts and any floor pan to jack against is quite high up.

[86 chevy silverado]

I just finished pulling the nose off my 86 Gmc and looking at the radiator support bushings they fit into the brackets on the frame, so this would mean you would have to use the proper bushings for the frame instead of the body.
If you do have an earlier frame you will want to maintain the early bushings as well.
The top pic are the early ones, lower pic is '81 up.

I jack up the cab with a block of wood (a couple if necassary) at the floor braces so I dont tweak the rockers, if you get it just right you can lift one side and replace both at the same time.

[Donut]

Sux, like Haulin mentioned, the upper mounts you pictured are for a 73 to 80 4wd. (I've got 3 out of 4 done on my truck now, just mine are the red ones.)

A popular catalog lists the poly bushings as this.
1# for 73-80   2wd  1/2 ton.
1# for  73-80  2wd  3/4 ton and 4wd (all)
1# for  81-87 2 and 4wd.

[HAULIN IT]

Sux, I'm wondering if what is in the second picture is the upper body bushing part of a body lift kit?

[Captkaos]

It would be much better if you posted pictures of what the bushings look like that you removed.  73-80 bushings don't have a metal "cap w/ integrated sleeve that the 81-87's use.
And yes, bushings are frame specific not body specific.

[HAULIN IT]

Chris, What is it on the frame/cab mount bracket that makes them different? I had bought all 12 pieces new from Gm for my '78 4x4. When I was preparing to do my body drop on my '85 2wd, I noticed that the Left rear mount was flat & split. I used the Four new 4x4 uppers (rad support & front cab mount) & The Two (rad support on the 4x4) lowers under the cab & reused Two of the old lowers. The rad support ones on the 2wd were still good. The hole in the frame was the same (round with Two flat sides) & I'm pretty sure I checked the part numbers on the uppers & they were the same...could this be something that has been grouped into one as the trucks are getting older? The total height has to be the same even though the one has the one piece washer/sleeve. Lorne 

[frogman68]

Bottoms one look like the S10 4wd ones

[Captkaos]

The differences in the 73-80 vs 81-87 is the hole diameter in the mount, and the height of the bushing, if that is what you are asking.

[SUX2BU99]

I plan to return the ones I have and pick up the 73-80 mounts today. I'll be able to compare them right there to determine which is correct for my application but I'm 99% sure the 81-up ones I have are incorrect to fit my frame.

[Donut]

It would be much better if you posted pictures of what the bushings look like that you removed.  73-80 bushings don't have a metal "cap w/ integrated sleeve that the 81-87's use.
And yes, bushings are frame specific not body specific.

My 73 4wd has what looks like a large washer w/sleeve on the rear mounts and radiator support, and just a large square washer on the front cab mounts.  Could this be a 2wd vs. 4wd thing, or something a P.O. thought I needed?

[HAULIN IT]

Chris, So the total height is the same (just the one has a "built in washer" so the rubber is a little shorter) & the outside diameter is the same (just the hole in the center is different based on the "built in sleeve") Is this correct? So '73-'87+ are really interchangeable as a unit, as long as you leave the bushings (being 2wd or 4x4, not the year) with the frame. Yes? This has been my finding. Lorne