I changed my radiator 2 days ago. Let me back up, on Saturday my radiator patch cracked and my Blazer overheated. I had it towed home and when I parked it tons of fluid poured out of the truck. Let it sit overnight (I was waiting for my new radiator to arrive the next day).

Here's when it became a transmission issue...

I went to start up my Blazer on Monday so I could do the work in the garage. It turned over OK, but then I shifted into DRIVE - nothing happened. Shifted into REVERSE - nothing happened. Finally had my neighbors push the darn thing into the driveway.

Radiator installed OK, but when I went to move my truck from the driveway - the same thing happened. It would move a little bit, but not enough to get it out of the driveway. Then my alternator died. I know, what a repair fail I'm having.

Replaced the alternator last night and put my battery on a tender to charge it up. Put the battery in today, the car turned just fine but the SAME ISSUE persisted. Finally, after pouring over forums, I put in ATF because I was painfully low.

Guess what, the car shifts into DRIVE and REVERSE. But, I'm still having issues accelerating past 30mph and I sense hesitation in my transmission.


My questions are...
1. Did I loose ATF when my old radiator died?
2. I have an ATF leak now, do you think it's related to the radiator repair (like not tightening a line?)
3. Should I just go to AAMCO and get the transmission fluid changed and have them check all the seals?

Thanks!

 

from what you describe it was definitely low on trans fluid it doesn't take much to cause poor shifting. if i were you i would try to find a nice level spot to put it let the engine warm up to temp and check the fluid level (engine still running) if its low fill it all the way to the full mark but try not to overfill. while your waiting for it to get to temp watch the lines from transmission to radiator if its leaking as bad as it sounds it should be fairly easy to find

 

Most Blazers have a transmission oil "cooler" built into one side of the plastic portion of the radiator (with an oil "cooler" on the other side). There should be lines from the transmission to the side of the radiator tank.


When you checked the transmission fluid, before topping it up, was it the right color and consistency (pink and smooth)? Did it smell burnt? Was there any sign of foreign fluid mixed with the transmission fluid? You mentioned that your radiator was leaking. Where was it leaking? Was there any sign of foreign fluids in the coolant? On my old Blazer, I actually developed an internal leak from the transmission cooler into the radiator, which pushed transmission fluid into coolant inside the radiator.


Like Chevy77 said, be careful to not over-fill the transmission when topping it up. Overfull can actually be worse than a little under-full.