Shifter movement and random thunks

[blk\blk90]

On this new 91+ I picked up the shifter seems to move around everytime I accelerate or let off the gas. I want sure if that's normal on a rod shifter since my other 91+ has a cable shifter. It also seems to kinda buck at low speed, but not engine bucking, like let out the clutch wrong bucking. And if you let of the gas or get back on the gas at anyspeed it kinda thunks. It feels harsh. From a stop, the instant weight transfer occurs there's a think from the rear end too. I tried the ebrake and let out the clutch deal and the motor moves a bit in both 1st and reverse, but my ebrake doesnt hold well so I couldn't try it that well. I'm thinking bad MMs, but could it be anything else?

 

[zoomlater]

Sounds like motor mounts, you can do a quick check with emergency brake on and hood open. Put it in first and slowly press on the gas and see if the motor move upward by more than an inch. Do the same in reverse.

 

[blk\blk90]

I tried it but my ebrake doesn't hold too well. Couldn't get a good look. It did raise in both directions though. Any way to check the trans mount?

 

[Irish Pride]

Look at the pad under the hood. If the engine is raising excessively you will see where it's rubbing on the pad. Eventually it will start to polish the intake where it's rubbing. Could be a combo of bad mounts and worn clutch/flywheel. My old 89 would buck like crazy whenever I would take off in 1st or reverse. Swapped in a new clutch and shosource flywheel and it shifted smooth after that. If that car has an aluminum flywheel that could be part of the problem too. They tend to flex when paired with the wrong pressure plate.

 

[zoomlater]

I tried it but my ebrake doesn't hold too well. Couldn't get a good look. It did raise in both directions though. Any way to check the trans mount?

Try blocking the wheels if the ebrake doesn't hold. You can see the trans mount when the front wheel is removed. From what I read, if the other mounts have failed, the trans mounts sees more movement than it should. I have yet to see a failed trans mount, but have caught a front mount failure a couple of times now.

 

[blk\blk90]

So I checked the hood pad. Definate rubbing. Problem is with the hood open, I can't see the bottom side of the hood and the intake doesnt show any signs of rubbing. I have a reinforced front and rear mount on the 92 I can throw in here. Would this be a good time to throw my AL SFBs in too? And should I worry about the trans mount? That shifter moved pretty good when getting on the gas in 2nd and 4th.

 

[zoomlater]

You are looking to see if the intake on the engine moves up or down more than an inch. The front of the intake should go up when in 1st gear, but not more than an inch.

 

[blk\blk90]

Yeah, it moves pretty good. Not as much in reverse, but it still moves.

 

[zoomlater]

Maybe only your front mount is shot, but there maybe other things going on as Irish Pride mentioned in his post

 

[blk\blk90]

I think the rear is bad too. After reading about it it sure sounds like both are bad. The clunk when letting of the gas is the motor falling back down. I think I'll pull the reinforced mounts off the 92 and put em on. And since it's easier to replace the rear by lowering the subframe I'll do my SFBs too.

 

[BaySHO Performance]

Never seen a torn tranny mount.

 

[blk\blk90]

I'll take a peek at it when I get in there. Judging from the movement and the hood pad, the motor mounts may have been bad for a while.

 

[FastCAD]

On this new 91+ I picked up the shifter seems to move around everytime I accelerate or let off the gas. I want sure if that's normal on a rod shifter since my other 91+ has a cable shifter. It also seems to kinda buck at low speed, but not engine bucking, like let out the clutch wrong bucking. And if you let of the gas or get back on the gas at anyspeed it kinda thunks. It feels harsh. From a stop, the instant weight transfer occurs there's a think from the rear end too. I tried the ebrake and let out the clutch deal and the motor moves a bit in both 1st and reverse, but my ebrake doesnt hold well so I couldn't try it that well. I'm thinking bad MMs, but could it be anything else?

The rule of thumb goes: If front and rear motor mounts go bad then the trans. mount should be replaced also.
Yes, I have seen a torn trans. mount on my '91 after I tore up my front and rear mm'ts. before going to reinforced mm'ts. I was told that my problem was the " nut behind the wheel" lol.
Alum. sfb's. are great for handling but they do make considerable noise at low speeds ie; parking lot speeds.

 

[FastCAD]

On this new 91+ I picked up the shifter seems to move around everytime I accelerate or let off the gas. I want sure if that's normal on a rod shifter since my other 91+ has a cable shifter. It also seems to kinda buck at low speed, but not engine bucking, like let out the clutch wrong bucking. And if you let of the gas or get back on the gas at anyspeed it kinda thunks. It feels harsh. From a stop, the instant weight transfer occurs there's a think from the rear end too. I tried the ebrake and let out the clutch deal and the motor moves a bit in both 1st and reverse, but my ebrake doesnt hold well so I couldn't try it that well. I'm thinking bad MMs, but could it be anything else?

p.s. Don't forget that after you install new engine mounts, check the (three) engine torque dampers for proper fit and adjustment.