knocking 700r4

[S. Burnham]

i have a 88 k5 blazer all stock including tires (due to lack of time and funds at this time). i have a very hard knock in my drivetrane at an idle(after warming up) and my oilpressure holds about 15 psi. when i start down the road the knocking goes away and the oil pressure does fine. until i get to about 55 every thing work great except for second gear has some sliping and some times third will slip. but it does not slip at all when driving like grandpa. when you get to 55 the is a hard vibration that travils throgh the drive train like ann unbalanced drive shaft. i have changed the tourge converter te oil pump and trans filter. ido not believe that the rear main is knocking i believe it is the trany. also after puting my foot in if the windows are down you can smell the trans baking from heat, but i have a cooler and it is bypassed the radiator. anybody ever heard of something like this or is this just another one of these things that just happen to me and no one else. any input would be greatly apreciated.

 

[dyeager535]

I've disconnected the torque converter and run an engine before, didn't seem to hurt anything, and eliminated the tranny as a cause of a problem.

I doubt it is THE problem, but when you replaced the converter, did you check to see if the flexplate was cracked?

To be honest, sounds like the tranny is toast anyways, and you are just on borrowed time. I'd start saving up, because once it starts slipping, you aren't in for a cheap fix. You can try that tranny fix in a bottle, but if you have problems in multiple gears, and the tranny is actually making noise, it's not going to fix it.

 

[S. Burnham]

yeah borrowed time is what i live on. i did check the flexplate and it seemed to be in good shape. i had someone els tell me to do the same thing today about unbolting the converter and cranking it but i think i am just going to start considering my options on motor and trans. i am in the process of trying to sell a house so i can start to work on this thing. i know it sound dumb, but i realy want to put a 5.9 cummins in it. fuel is getting to expensive to try and build a high torque gas burner. i haven't decided yet but i appreciate the advice.thanks