Drive-shaft forward and back?

[Motorbreath]

I just took my car in because i was getting worried about the driveshaft/transmission, when i'm at a constant coasting speed between 25-30 mph it works fine but if i lightly tap on the gas to speed up it feels as if my driveshaft/transmission is moving forward and backward, it only does it at those speeds? i thought maybe it was the u-joints but those were in working condition, i replaced the transmission mount, the mechanics didn't even know what it was, they said the it might be the engine and it may need a tune up, i was thinking what does that have to do with what im talking about, they maybe right but i don't think so in my opinion. So i told them im going to get some experts advice on this specific car. Does anybody else have this issue?

 

[Steve V]

Is the trans hunting 2-3..3-2..2-3.3-2...etc? Thats' what it sounds like.

 

[Motorbreath]

Im not to familiar with the term trans hunting, but i looked it up (slipping or stumbling between gears at low speeds). Stumbling between 2-3 gear or vice versa, that sound's like it's the problem.

 

[Steve V]

Stock trans? Does it have a shift kit? If it is stock maybe some trash in the VB, if it has a shift kit I 've seen this on EVERY single one I've used. The only fix I know of is returning to the stock size feed holes in the separter plate.

 

[Motorbreath]

stock trans, as far as i know, im the second owner

 

[Steve V]

Only way to tell for sure is to remove to the valve body and look at the separator plate.

 

[SFI Cutlass]

Sounds like a torque converter. I had that same issue on my diesel excursion and I added a bottle of lubegard oil additive and it went away. No more confusion between the shifts and felt smooth right away. A buddy of mine added it to his Gn and loved the way It shifted, it was a stock motor with lots of bolt ons and a stock trans. I would try that route first the additive is only around $15.

 

[Buick Mark]

From your description, from my experience, it sounds like it could be the torque convertor clutch solenoid.
Does it does this only when the trans is fully warmed up? (As in getting off the highway after about 20 min.)
Does it feel like it going to stall right before comming to a stop?
Does it buck and lurch when stepping on and off the gas, like a standard trans?
Does it short shift when fully warmed up? Fiiiiiiiiiiiiiiiiirst-Second-Third, then it starts lurching?
Its a very common failure part on 200-4r trannys.
About 35 to 50 bucks for the part, AND you can do it yourself. Drop the trans. pan, unplug a couple wires, replace valve.

 

[Motorbreath]

buick mark, i think your right it does quite a bit of those things so i might just replace it and sfi cutlass i'll probably take your advice to and just add the oil additive to

 

[Motorbreath]

ill let you guys know how it goes once i change the valve

 

[Buick Mark]

Hope it fixes your problem, let us know

 

[Ttype6]

ill let you guys know how it goes once i change the valve

Disconnect the electric connector on the drivers side of the trans then take it for a ride. If your symptoms go away,you have a bad solenoid.

 

[SSedan64]

X2^^.
TCC Info > http://www.montecarloss.com/TCC_Solenoid.html
The OEM Solenoids w/Harness are no longer available, get a Universal splice type if needed.
http://www.makcotransmissionparts.com/54425B.html
http://www.makcotransmissionparts.com/T54425B.html
https://www.wittrans.com/SchematicParts.aspx?Transmission=200-4R&LinkCode=425
http://www.transmissionpartsusa.com/2004R_transmission_solenoids_s/4847.htm

 

[Motorbreath]

ill disconnect it thursday and take it for a spin and get back to you, but i already ordered the tcc valve from kirbanperformance

 

[Motorbreath]

Well i unplugged the switch on the side of the Trans and it works great now, now i just have to wait for the part to fix it