I know I have discussed this before but I still have yet to find a fix!

When I engage the transmission to Drive or Reverse, the car jerks forward. The harder I press the brake while changing gears, the less the jerk, but still very noticable (and besides, I don't think I should have to press the brake pedal that hard anyways!)

I have heard that another cause of this is high rpms when shifting to Reverse/Park ... my rpm meter reads 900/850.

I have changed all the mounts (engine and 2 tranny mounts).

There has to be a reason for this because I am sure a brand new Fiero wouldn't have this problem.

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1986 GT Fiero Owner & Enthusiast
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How's your Dogbone? Have you had someone watch the engine as you shift into gear to see if its moving at all?


How long does it take before the transmission actually engages?

Also added new dogbone bushings.

It takes 1 or 2 seconds... my only concern is the jerk... after the tranny jerks, it indicates I can remove my foot off the brake pedal basically.

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1986 GT Fiero Owner & Enthusiast
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I've had it happen before, and both times it was the front transmission mount, and a bad dogbone. You will have to get someone to put the car in drive while you stand at the back to see what is actually moving around. I suppose it could also be caused by bad cradle bushings or loose fasteners, but I haven't personally seen that be the case.

Read somewhere on here a couple years ago, that a guy had it happen, and it was loose bolts between eng and transmission.

The dogbone needs to be really good quality, and the bolts need to be tightened down to just before the breaking point-literally. I have found that the dogbones sold at chain type auto parts stores aren't worth a crap. They come with the bushing sleeves that are smooth on the ends--not serrarated like the OEMs were. They just don't 'bite' into the mounts like the OEMs did. When I change a dogbone out, I try to re-use the original sleeves.

Maryjane...

can you give me a little more information on any potential lose bolts between the tranny and the engine so I can do it.

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1986 GT Fiero Owner & Enthusiast
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bump for more help... there's got to be more people with the same issue

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1986 GT Fiero Owner & Enthusiast
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Put it in neutral. Does the RPM flare when you drop it into drive and then go down to about 750?

The solution to my brother's identical problem was the torque shock on the front, near the oil filter. His was missing. I added one to it and the problem went away. Might be that yours is missing, worn out, or the bolts are loose. A previous 85 I had had a clunk when starting or changing gears. The cause was the shock mount to the cradle was missing its bolts.

I don't think 85's had them in the first place unless it was auto only in 85.

quote Originally posted by chrismclubm: Maryjane... can you give me a little more information on any potential lose bolts between the tranny and the engine so I can do it.

Not much. Been a couple of years since I read about it, but if memory serves me right, the bolts between engine and torque convertor housing had either gotten loose or were not tightened down correctly after some repair work was done.

The loose bolts could cause this ,also the dog bone is the first thing to check,, you may have to lift the tranny and engine up to check for mount rubber broken.. when you have any type of problem with a stock fiero transmission always check the T V ajustment . and fluid level when hot,,check vacuum line,,check TV cable for smooth action,,lube or fix kink,check shift linkage..a bad modulator causes harsh shift,,check vacuum line for fluid this is sign of faulty modulator..
it is NOT the governor
With engine running check for engine vacuum at modulator,,if not strong there is a leak

[This message has been edited by uhlanstan (edited 08-06-2008).]

quote Originally posted by TK: I don't think 85's had them in the first place unless it was auto only in 85.

I've had 2 original 85GT 4-speeds and they both have the shocks between the front of the engine and the cradle, near the AC compressor and oil filter, as does my 87GT 5-speed. My brother's car is an 86GT auto. A friend's 86GT 4-speed also has the shock. Don't know if it's standard or not, but they were on all our cars when we bought them, except for my brother's. In any case, when we added it to the 86 auto, it solved the problem for us.

So I guess the main problem causing this jerk is the shock absorber :S I would hate to have the same problem after installing a new one, that's for sure!

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1986 GT Fiero Owner & Enthusiast
For Fiero updates, visit my site and don't forget to click on the ads!
http://educatorstop15.we.bs/fieropage.htm

quote Originally posted by chrismclubm: So I guess the main problem causing this jerk is the shock absorber :S I

Not necessarily, but it's one area to look at along with the ones others have suggested.