Drivetrain Bucking and Lurching.... ???

[Katmandu]

When driving my 91GT (w/T5) at slow speeds, the drivetrain occasionally starts lurching and bucking. This typically happens around 5-10MPH in while in 2nd gear and around 10-15MPH in 3rd gear.

The U-joints are good and tight as are the transmission/motor mounts. A local mechanic blames low gears (3.73s) that are in it.

What could be causing this ??

 

[jrichker]

You need to downshift into a lower gear. The engine is trying to stall because there is too much load on it for the RPM's that it is turning.

 

[302RollinHard]

also if you have a moderate cam in your car, the bucking problem will be magnified.

 

[Katmandu]

You need to downshift into a lower gear. The engine is trying to stall because there is too much load on it for the RPM's that it is turning.

I "think" that is what the mechanic was trying to tell me.

I should have mentioned that there is a clanking noise coming from the rearend area when this is going on.

Is this "normal" then ?????

 

[302RollinHard]

fairly normal. There is some lash built into the rear end. That is probably your clanking noise. However, if it is really loud, I would have it looked at.

 

[iwashmycar]

mine does the same thing...same gears...ect. Just have to keep the rpms up, which is a pain in traffic/stop and go situations

 

[NKau]

The bucking is normal, but again, just keep the rpms up at low speeds, and it won't be a problem. The clanking is normal; your rearend, and even tranny probably have enough 'looseness' in them to do this. Just make sure the u-joints are indeed OK.

 

[Sicarius428]

The clanking is your drivetrain slop most likely. It is normal because there will always be a bit of play from the engine to the rear wheels. It's loading up the gears and letting off over and over so it is really amplified.
Kevin

 

[Flavadave4]

Mine does the same if you let out the clutch and go with no throttle, give it the gas and its gone!

 

[Katmandu]

mine does the same thing...same gears...ect. Just have to keep the rpms up, which is a pain in traffic/stop and go situations

I'm used to driving around in my Dodge Ram w/Cummins Turbo Diesel. That thing can pull a house down at 1000 RPMs! The low-end torque is ungodly!



My Stang is mainly a weekend fair weather cruiser, so I guess I gotta change low RPM driving techniques then!

Here's a pic of my Cummins Turbo Diesel Ram....

http://www.katmanduonline.net/pics/98_Ram/

 

[Black1987Stang]

mine does the same thing...same gears...ect. Just have to keep the rpms up, which is a pain in traffic/stop and go situations

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