MazdaRx7Power

ok whenever i shift gears or have my foot on the gas pedal just a little when shifting gears, i hear a clunk and my car shakes a little along with that clunk. so i'm thinking its the rearend mounts that are bad. is their just one or do i have to buy to of them. cause i heard if u keep driving it like that ur gonna break ur rearend. plus its annoying feelin a clunk everytime u drive and shift gears. so does anyone know what i have to buy and how much it is at the dealer and if i only have to buy one or if their is only one , hate waitin for mail orders?

HAILERS

If you determine its the differential mounts, there are three of them. The front one is one of those that is a bear. I found that if I put the rear of the car on jack stands, really secure, start the engine and put in gear, that if I have someone tap the brakes, I can see the differential jerk in an upward motion in the front part of the differential. You can then see the seperated rubber on the mount. The two ear mounts on the rear of the differential are childs play to change or check. The front is a bear. All cost the arm and a leg. Could be its something else like the driveshaft ujoints or the half shaft ujoints.

MazdaRx7Power

how do i know if its the driveshaft thats messed up?

XimbueX

If you get under the car, you can inspect the U joints in the driveshaft but getting a good look at them and making sure there is no play when you turn the driveshaft, if its bad it will be apparant.

Another cause of clunking could be your tranny mount, its the crossmember that bolts the tranny to the frame. Push up on the tranny, if there's a lot of play between it and the crossmember, then its probably bad.

As for the diff mount, if you can move the diff up and down by any signifigant amount, then it is bad. When you accelerate and put a load on the drivetrain the diff moves up and smacks the bottom of your car. It's a pain in the *** to change, you have to unbolt half of the rear subframe, and pull it down enough to access the mount, which is on the top portion of the diff.

Scott 89t2

it sounds like the front diff mounts. get the mounts from www.mazdamotorsports.com they don't have them listed but the front diff mounts are not that much. just call them. you need 2 of them. they are 40% stiffer then stock and won't break again. also will give you better throttle reponce.