tranny not shifting well.

1989 buick lesabre.

when shifting from 2nd to 3rd the car appears to go into neutral and rev up without shifting up.

i've been told the input drum may be cracked or the clutches are burnt (tranny fluid smelt a tad burnt). the mechanic who took a look said that they could rebuild the tranny for around $1500 (i only payed $1000 for the car 3 months ago) or i could go to a scrap yard and get a tranny for around $300.

i don't have the cash to rebuild the tranny (which would be the better idea right?) but if i go to the scrap yard and get a used tranny - what kinda tranny should i be looking for? how many km's? what should i check for? the warranty on a tranny from the scrap yard is only 30 days - is it even worth it to get a new tranny... i could always just leave it in 2nd till i get to 80 and then shift to overdrive.....

i heard trannys on the lesabre's go all the time and this is a common problem, if i do get a tranny from the scrap yard how can i prevent this from happening again and why are these trannies so fragile?

If the fluid smelled burnt, then the 3rd gear clutch plates have stripped because of a problem that was only recently (to my knowledge) fixed. There is an actuator valve in the older trannies that was about 1-1.5 inches in diameter, and about 3 inches deep. This valve was to pump fluid to different internal parts, and because it had a small diameter, it had to pump deeper to get the neccesary fluid to the parts. So, that also means pumping faster. The faster it goes, the more wear is incurred. It would eventually wear out the spring that pushed it back, breaking it. That metal would then be carried through the tranny, eventually getting mostly caught in the filter. However, now the valve is improperly functioning, and cannot produce enough pressure to satisfy the parts it was previously feeding. That would cause too low of a pressure to properly engage up to all 4 gears, resulting in stripping of the clutch plates. The metal flakes not caught be the filter tend to speed this process up. Eventually, you lose a gear or two or three. Second and third gear are usually the first to go.
That is the "why", and this is what I recommend.
Unless you have a chassis service manual, and know what you're doing, you will have to have someone rebuild it for you, or get a used one from a junk yard. What to look for at a junk yard
1. realize that these trannys last between 130,000 to 170,000 on average. The motor can last up to 350,000 miles if well taken care of.
2. Brown/ smelly fluid = death soon. don't buy.
3. avoid 130,000 to 160,000 miles on the odometer.
4. find a car that is there b/c the motor died. usually these will have already gone through a tranny, and are on #2 or a rebuilt.
5. CHECK THE FLUID!!!
6. re-built are better to go with. chances are they were done recently (relitive to the time they were scrapped), and have plenty of life in them yet.
7. Check the fliud!!!
8. if you get one from the junk yard, change the fluid and filter right away, before you even try to drive it! Need about 9-13 quarts total. Check the fluid level with motor on, tranny in park. fill it according to the dipstick. Put one container of Lucas transmission treatment in in place of 1 quart of tranny fluid. This should help prevent any damage from the tranny sitting for however long in the scrap yard.
9. If at any time during the warranty period you notice any problem such as bad shifts or slipping, take back to the junkyard right away.

-or-
spend $1500 to rebuild it. Not neccisarily the "better" choice, as most mechanics don't do alot with trannys. better off to go to a tranny repair specialist. Just remember to get the tranny flushed every 50,000-70,000 miles, no matter what you decide to do.

I didn't mean to write a book, but hope it helps you nonetheless.

very very good reply and i thank you so much for the info.