Q: How to replace rear main oil seal on 4.3L V6 engine for Chevrolet Avalanche,Silverado,Suburban,Tahoe,GMC Sierra,Yukon,Yukon Denali and Yukon XL?
A: Remove the transmission and the driveplate. Inspect the oil seal, as well as the Oil Pan and engine block surface for signs of leakage. Sometimes an oil pan gasket leak can appear to be a rear Crankshaft Seal leak. Pry the Crankshaft Seal from the block with a screwdriver, being careful not to nick or scratch the crankshaft or the seal bore. Thoroughly clean the seal bore in the block with a shop towel, removing all traces of oil and dirt. Lubricate all surfaces with a very small amount of engine oil. Install the Crankshaft Seal over the end of the crankshaft and carefully tap it into place. Most seals are marked "This Side Out" to eliminate confusion as they have a different design than the old-style seals previously used. The tool tightly fits the diameter of the Crankshaft Seal and, used with a hammer, drives the seal in. Install the driveplate and the transmission.
Q: How to replace rear main oil seal on V8 engine for Chevrolet Avalanche,Silverado,Suburban,Tahoe,GMC Sierra,Yukon,Yukon Denali,Yukon XL?
A: Remove the transmission and the driveplate. Take a screwdriver and pry the Crankshaft Seal from the rear cover without nicking or scratching the seal bore, or crankshaft. Note how far it is recessed into this housing bore prior to removal so that the new seal can be set at this depth. Grab a shop towel and thoroughly clean out all traces of oil and dirt from the block's seal bore. Do not lubricate the seal or touch the sealing lip. Make sure that it is installed properly as it has reverse-lip design on it. The second requirement is that you must see its part number when this seal has been installed. The best way to do this is to use a tool for installing seals to fit in this new one by pushing the tool onto it until it goes back into its place completely. In case, there isn't an appropriate seal installing instrument, one can take a big drift and softly drive this new seal directly into its bore located near rear cover; after which, flush them together so they appear even with one another. Finally, install drive plate and transmission again.