Hey, I have a 96 blazer 4.3 L 4x4 with 107,000 miles and deff. have a minor to substantial oil leak. I've tightened all of the bolts on the oil pan and the plug itself. What else should I be checking and how should I be checking it? If it's a gasket or seal, how hard are they usually to replace? Thanks

 

Your Blazer should have an external oil filter mounted on the driver's side firewall. The lines for that filter run back along the block to the rear of the motor. Check those lines out. Another idea is to get a big, clean piece of cardboard out and slide it under the front of your truck, this might help you isolate the area your leak is coming from.

 

Thanks, I'll have to check those lines tomorrow.

 

The cardboard trick is a good one! Just don't do it if you park outside and its supposed to rain (been there, done that).

The lines are a known problem for these trucks. The crimps aren't the best. There are several options for repairing them, ranging from cutting off the outer crimp and using a hose clamp, cut off the whole crimp and using AN fittings, brazing on hydraulic fittings and having hoses made up, or replacement with new aftermarket or oem lines (ranging from cheapest to most expensive depending on the availability of parts).

If it isn't the lines, you really should use some degreaser to clean the engine to make it easier to determine where it is coming from. You can put a UV dye in the oil and use a black light to further determine the leak location if it is not apparent after the cleaning.

 

Thanks for the advice swartlkk, I never knew there was a UV dye that could be put in with the oil. Sounds genious! Alrighly well I'll check those lines later today and hopefully find the culprit. Thanks!