Firstly, I searched and mostly what I found was rear ends clunking or whining or making general noise that is easily ascribed to a rear end about to barf on itself.

When I first get in my car after it's sat overnight, for the first few 1-2 shifts it feels like the rear end "jumps". That is the only way I can describe it. I have a feeling that something is broken back there as not too long ago I got a wild hair up my butt and decided to floor it on the first 1-2 shift, got it to 5 grand and had a slight fishtailing incident (road was dry as bone). Left rubber on the road, for the right side only.

Here's the weird thing- after about five or six 1-2 shifts, it goes away and doesn't return until the car gets cold again. Like, I could let the car sit for six hours and it won't do it, but if it sits overnight I'll have this issue again. For the first, and sometimes second 1-2 shift, the motor will wind up as high as 3k RPM before it actually goes into second. Like I said, after five or six shifts this all stops and it shifts and feels pretty good for being 28 years old. This pattern has not changed one iota in the nine months I have owned the car, nor did it change when I did tranny service. There are times where I have redlined it and on that shift it feels like the car is going to vibrate apart but I think that's either my lack of SFCs or a bad trans/motor mount.

What gives? I'm stumped

 

Ring gear teeth
Best bet pull the cover

( edit )
Clunk sounds & jerk sporadically?

 

You have transmission problems, not rear end problems. You are looking in the wrong place.

 

No clunking noise. It just "jumps". Like I said, it stops after five or six 1-2 shifts. Only happens after the car sits long enough to get bone cold. Never randomly happens. If it describes the problem any better, it almost feels like the rear end pivots or something. Like the right wheel twists in towards the center of the vehicle, left wheel twists out as if you were spinning the rear end counterclockwise on a central axis.

I have to yank the cover this weekend to swap the fluid anyway so I'll poke around a bit in there and see if I see anything nasty. I'm kinda leading towards a u joint or something but this honestly has me at a loss. Granted, this is only the second RWD vehicle I've owned so I don't really know how to diagnose rear end issues. I doubt it, but could it be doing this because my car doesn't have a panhard bar? I'm pretty sure the PO didn't install one or LCA relocation brackets when he dropped it.

 

I thought the same thing at first too, but I wouldn't think the trans fluid gets hot enough after a few 1-2 shifts to make everything smooth back out. I have no nasty fluid smells, it looks normal, there were negligible shavings in the trans pan when I dropped it two months ago. And it's not even like these first few shifts are just "BANG BANG BANG" into gears, right after the other. The first 1-2 shift is the hardest and the only one that will get the motor to 3K- and even that is something I have to try at, I essentially have to "work" the throttle to get it to do it. If I accelerate normally and let off at normal shift RPM it shifts, rear end jumps. The next 1-2 shift I perform still gives the "jump" feeling but it is nowhere near as weird/odd. Usually by the third or fourth time I perform a 1-2 shift it is gone. Now that I am thinking about it, it has never done this after the third 1-2 shift. I asked my fiancée who drives the car much more than I do and she confirms that by #3 1-2 shift the issue is gone, and there is no jumping or shenanigans.

 

Gotcha!!
Pump going bad, bands // clutches...?

 

There is nothing in the rear end to cause a problem like this. A rear end is either broke or it's not. It doesn't act up for a while and then work fine. When it breaks it stays broke. You have a transmission problem.

 

You don't have a transmission problem.

You have a transmission MOUNT problem.

Replace the mount.

 

Yea, the first thing I thought of was the mount, but it didn't make any sence that it would only do it about 3 times and then quit when it warmed up. It could very well be the mount. That's the easiest thing to try and would be the best place to start.

 

Thanks for the suggestions guys. I will do my motor and trans mounts and see if the problem persists.

If it does, should I start replacing clutch packs or...? I don't want to start throwing parts at it but at the same time if the consensus is that its probably a trans issue, it probably needs to be refreshed anyway

 

Replace the trans mount first; worry about the rest later. (if at all)