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Topic Review (Newest First)
05-01-2013 08:43 PM
Torque454 The Dana 30 is the OEM rear end. I just mentioned it in case it meant anything to anyone. Some rear ends have an offset to one side although i don't know that this one has that. There is a lot less drive shaft clearance on the passengers side of the car than on the drivers side tho. I tend to agree that its probably a spring/suspension problem tho. I think it squats way too much under acceleration. The more I look at the car tho the more i think it IS sagging in the rear. Here again I don't know if its the suspension or if the Chevy engine just doesn't weight as much as the Volvo engine did which would cause the front end of the car to not sit as low as it should.

BTW the car is a 265 (2 series, 6 cylinder, 5 doors) which is a station wagon so it already has station wagon springs under it. They could be old and saggy tho never know.
04-29-2013 08:01 PM
PatM You mention it's on the passenger side, and that the rear end is a Dana 30. I assume that Dana didn't produce OE read ends for Volvos. I'm thinking a heavier duty differential/rear end (perhaps shifting the driveshaft sideways a bit) combined with a larger diameter driveshaft is the cause. Have you considered a smaller, custom made driveshaft? A little shift combined with a driveshaft about one inch oversize . . . I can easily imagine this collision happening against the tapered (passenger) side of the tunnel.

PatM
04-29-2013 06:39 PM
gearheadslife I'm not up on volvo's but iirc it's a unit body.. and if the drive shaft is rubing at the rear. nothing from the engine swap caused that..
now springs settle over the years from age and from holding up the weight for 33 years..
might try to find the factory ride height.. and see where your car is compaired to what it was new, it might have settled an inch or more..
you could also have a cracked(broken) coil on that side..
you might be able to install new 1980 volvo wagon springs to give little less drop when you have a full crew in the car..
I'll bet you'll find the 33 year old springs have saged and weakened over time.
install new wagon springs(if they fit) or new replacements for your model and the problem will go away..
04-29-2013 05:32 PM
ericnova72 You could put Air Lift air bags inside the stock spring. An old racers trick to increase spring rate.

You can add or subtract stiffness just like air shocks.
04-29-2013 12:03 PM
toddalin This is a very common problem on old Corvettes after the bodies start to sag and the bushings compress. The way a Corvette's rear suspension is set up, they go "squat" under load and this is common.

For the Corvette the quick and simple solution is to remove the front nut and slide back the bolt that holds the pumpkin's carrier and slip a couple fender washers between the carrier and the bushing. This spaces the carrier, rear end, and U-joint down a hair and gives the needed space.
04-29-2013 11:16 AM
Torque454
Quote:
Originally Posted by MARTINSR View Post
If you want the ride height where it is then getting a stiffer spring is about all you can do. If it's squatting too much, what else can you do to correct the problem but stiffer springs? The new shocks could help but in the end you need the rear to not go down as much. Opening up the drive shaft tunnel or making the drive shaft from a smaller tube will stop it from hitting but it still doesn't stop the rear from squatting too much. It will still squat too much with the rear of the car going down too much, the drive shaft just won't hit anymore.

So figure out what you want to do, correct the problem, or leave the problem and make it work by giving the drive shaft more clearance.

I am not being a smart aleck here, if the squatting isn't that bad you may want to live with it and simply create a little more drive shaft room.

But understand it may look like it is "barely" hitting the tunnel and you "relieve" the tunnel with a big hammer and you find out it is still hitting, then you relieve more, and it's still hitting.

If you are fine with a little more height in the back then some spring spacers under the spring and raising the back of the car a little may do the trick. But what happens when your BIG friend gets in, it's going to hit again!

Is the rear end moving from side to side when the rear of the car goes up and down? Did you change the rear suspension at all or is it original? The rear end could have a locator bar that is at an angle and the rear is going over to one side when the rear end goes up? Take a look at that too.

Brian
This is partly why i am having trouble with this. The car seems to be riding at normal height, it doesn't appear to squat in the rear. So i don't really think the springs are bad, and there aren't really any other springs available for this car - there isn't much aftermarket stuff for it. I can get new factory replacement springs from the parts store, but I don't think that will solve my problem. I thought about air shocks but i cant even find any of those for this car.

Due to the fact that I cant seem to find any stiffer springs, i figured the only option was probably changing the drive shaft diameter (who knows, it might be bigger around than the original one was IDK, i didn't put this engine and transmission in this car.) or lifting the rear or something.

The rear suspension is all original so it should be fine.
04-29-2013 10:20 AM
timothale
rubber pinion bumper.

you might look into installing a rubber pinion bumper that will take the bump and be compressed just before the drive shaft hits the floor.
04-29-2013 09:17 AM
MARTINSR If you want the ride height where it is then getting a stiffer spring is about all you can do. If it's squatting too much, what else can you do to correct the problem but stiffer springs? The new shocks could help but in the end you need the rear to not go down as much. Opening up the drive shaft tunnel or making the drive shaft from a smaller tube will stop it from hitting but it still doesn't stop the rear from squatting too much. It will still squat too much with the rear of the car going down too much, the drive shaft just won't hit anymore.

So figure out what you want to do, correct the problem, or leave the problem and make it work by giving the drive shaft more clearance.

I am not being a smart aleck here, if the squatting isn't that bad you may want to live with it and simply create a little more drive shaft room.

But understand it may look like it is "barely" hitting the tunnel and you "relieve" the tunnel with a big hammer and you find out it is still hitting, then you relieve more, and it's still hitting.

If you are fine with a little more height in the back then some spring spacers under the spring and raising the back of the car a little may do the trick. But what happens when your BIG friend gets in, it's going to hit again!

Is the rear end moving from side to side when the rear of the car goes up and down? Did you change the rear suspension at all or is it original? The rear end could have a locator bar that is at an angle and the rear is going over to one side when the rear end goes up? Take a look at that too.

Brian
04-29-2013 01:48 AM
techinspector1 Gearhead has the answer I like. KaWhamm the hell out of the sheetmetal with a BFH. If you can't fix it with a hammer, you have an electrical problem.
04-28-2013 11:57 PM
S10 Racer
Quote:
Originally Posted by Torque454 View Post
I have a 1980 Volvo 265 with a Chevy 4.3 and 700r4 in it. The rear end is a Dana 30. Has a custom made drive shaft. If you put very much weight in the car, like a person or two, and take off very hard or accelerate too much, there is a loud noise inside the car and today i discovered that it is the drive shaft rubbing the inside of the trans/drive shaft tunnel, on the passengers side in the rear. I don't really know how to go about solving this issue?

With no one in the car there is a lot of space between the drive shaft and the tunnel (a couple inches), but add some weight and that space quickly diminishes. I guess the springs are too soft or something? They are coils, front and rear. I doubt new springs would solve the issue as it doesn't really seem to be sagging, it just has alot of bounce to it. I am thinking that i need to make or buy some spring spacers to raise the back end of the car a little, or have a drive shaft with a smaller tube made? or perhaps have one made that telescopes in the back half so that the back part would be much smaller than the current tube.

This is all i can really come up with. Any other ideas or suggestions?
I would start out by replacing the shocks since you said there is a lot of "bounce". There should be no bounce at all with good shocks.
04-28-2013 11:31 PM
gearheadslife BFH
04-28-2013 09:14 PM
Torque454
Driveshaft hitting the tunnel

I have a 1980 Volvo 265 with a Chevy 4.3 and 700r4 in it. The rear end is a Dana 30. Has a custom made drive shaft. If you put very much weight in the car, like a person or two, and take off very hard or accelerate too much, there is a loud noise inside the car and today i discovered that it is the drive shaft rubbing the inside of the trans/drive shaft tunnel, on the passengers side in the rear. I don't really know how to go about solving this issue?

With no one in the car there is a lot of space between the drive shaft and the tunnel (a couple inches), but add some weight and that space quickly diminishes. I guess the springs are too soft or something? They are coils, front and rear. I doubt new springs would solve the issue as it doesn't really seem to be sagging, it just has alot of bounce to it. I am thinking that i need to make or buy some spring spacers to raise the back end of the car a little, or have a drive shaft with a smaller tube made? or perhaps have one made that telescopes in the back half so that the back part would be much smaller than the current tube.

This is all i can really come up with. Any other ideas or suggestions?

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