Ok, when you change gears, or let off the gas at all, the car jerks. When I downshift, there is a clunk in the rear, and at about 2000 RPM in first, or any gear, it will jerk so bad it feels like my neck is gonna break! There are no problems w/ clutch or tranny as a new clutch was installed about 3 weeks ago and the shop said the tranny was solid. I am purchasing the front mount from a guy, I just needed some verification that this is the problem.

 

the jerking might be an out of adj TPS. the clunk is likely the front diff mounts.

 

But my TPS is solid. Trust me, I spent weeks getting that little
B*$#H to work right! I was under the impression that there is only 1 front mount! I hope so, cuz they are hella-expensive!

 

Get under the rear of the car. Push on the driveshaft near the diff. If it moves up, it's the front diff mount.

I had one break on me, right where the rubber meets the plate. Fortunately, the bolts prevent it from moving too far, but it's annoying as **** and will eventually damage something.

Ren

 

there is a pair of them in the front, a pair in the rear, and I heard there was a center one too. the clunk is most likley the front pair. I think about $30 each from mazdacomp and they won't break again.

 

Really? The Mazdatrix page, several guys on the forum, and the guy who owns the shop that I am buying my new one from all said there are two in the back, and one in the front! I tried pushing on my diff on the actual gear housing, and it didi not move. Duh, I should push on the front, if it is the front mount!!!!

 

Ok, I just went to my FC, and pushed likr hell on the diff from all angles, and the damn thing would not move more than 1/2 on inch upward! But I get a clunk when I put her into first when I am rolling (after backing up)! I'm baffeled!

 

1/2" seams like a lot to me...

if the clutch is in while you get the clunk it has nothing to do with the diff. I think anycar will do that. the front diff cluck will come when you hit or let off the gas while driving.

 

So, should I go through with the purchase? The guy is selling the front differential mount for $55 shipped? Also, there is no clunk when driveing, only jerking when I let off the gas! Hey Scott, is 1300cc.com yours? I love it! It is in my top 3 favorite sites!!!

 

I don't think it'll fix the jerking. my car jerks too when I let off. if it's not clunking I doubt it's broken.

yes the site is mine. I just wish I had $$ to buy more parts and to do stuff to my car so I can add more to it.

 

Soooo, what do I do? My neck hurts!

 

learn how to move your right foot slower

 

But how about when, I take my foot off the gas, or try to maintain a constant speed? It jerks then too! It's getting to the point that I actually hate to drive my 7!

 

Also, I have tried to take my foot off slowly, but it still jerks a little! GRRR!

 

mine jerks, I think all cars will. it more likely to be wear in the u-joints, rear diff, and half shafts. or it's to do with the airpump and afterburn system.

 

So, should I just go a tranny and drivetrain shop and ask?

 

1. Jack up the rear of the car.
2. Put jack stands under the car, not ramps.
3. Start the engine and put in 2nd gear.
4. Lay down beside the rear of the car and stare at the front of the differentials front end.
5. Have somebody tap the brake with the engine running and in second gear.
6. If the front mount is bad you'll see the front of the differential rise up and strike the bottom of the chassis. You'll see the rubber on the front mount seperate from the metal it WAS once bonded to.
7. You'd have to pay me three hundred bucks plus the parts to change one out. I've done two on my cars. I'll never ever jack one of my cars up using the differential, don't care what the Mazda manual says.
8. Its a simple check out and only takes thirty minutes. Take it to the shop and that thirty minutes will cost you.

 

So the car has to be off the ground to work, eh? I tried pushing up on the diff w/ it on the ground, and it only moved about 1/4 an inch (I know earlier I said 1/2)! I hope I don't need a diff mount, cuz I had a great deal on one untill I told the guy I couldn't buy it about 10 minutes ago!!!!!

 

You need to think about what that broken differential mount is doing to your u-joints on your driveshaft. If you've ever seen one as described in my earlier post, you'll see what a bind it is putting on the u-joints. Price a new driveshaft at Mazdatrix.com. Ain't cheap. Then again, maybe you don't have a broken front mount. You'll never know until you look. Thirty minutes max. I've done it by myself using a long pole to tap the brakes while looking at the front mount. Piece of cake.

 

I have no jack stands, or a floor jack. So, any other way I can Check?

 

I think all cars that are stick will.