"catching" feeling during easy takeoff

[LanceB]

I have a 77 L82 that is my brothers that I am trying to help him get up to speed. He keeps it in my garage next to my sparkling 81 but mechanically his needs some TLC. I noticed that when I am idling at 0-5 mile per hour and give it gas slightly, it will have a "catching" feeling. It only does it on easy acceleration and I don't really notice it on a faster takeoff or anything at all on the highway. The brakes were leaky and l thought it was maybe something there, but all were replaced over the winter and this strange catching seems to still be happening. It does not do it all of the time and it is hard to figure out just what causes it. The only thing I noticed is when it goes from a rolling idle to moving a little bit, it will act up. I suspect it may be coming from the transmission/rear end area, but really lack a way of troubleshooting. Transmission has a leak and I think what I call a "catching" feeling could be some form of slipping or having trouble engaging in from idle to moving in gear? Or maybe the rear end is having a problem. I suppose I could take it to a mechanic but trying to avoid major costs yet without some research. It has been doing it for a long time (years but not driven much unfortunately) and nothing has broken yet. Hate to see it happen when in use though. After one winter I noticed the transmission fluid was almost all drained. The rear end has had different gears installed recently, but the occurence happened before and after that. I really want to get this car road worthy!

 

[wishuwerehere82]

Lance,

That sounds like the front pump on the transmission is starving for fluid, or getting weak and causing the clutches to slip.
I assume it's an automatic. Turbo 350?
You could try dropping the pan and changing the filter, fluid and pan gasket on the transmission as a start, and it might fix the problem.
It might also be low on fluid, since you know it leaks.
Where does it leak? Front, rear, dipstick gasket or speedo cable?
Maybe just a pan gasket, but it could be an input shaft seal, which would require pulling the tranny, or an output shaft seal which requires dropping the driveshaft.