MY TURBO WAGON HAS AN OIL LEAK AT HIGHWAY SPEEDS. I REPLACED THE OIL FILTER WITH A FACTORY ONE BUT THE LEAK PERSISTS. ANY HELP WOULD BE APPRECIATED.

My 83' Turbo also recently had a huge oil leak. It caused smoke at highway speeds (and non highways speeds) beacuse the oil would hit the exhaust system, and then be drawn under the car out the back. It turned out to be the brass connector between the oil pressure sending unit, and the block. This piece was cracked, causing oil to come out at 60psi. Also, any smoke on upshifts or high vacuum situations can be caused by leaking valve guides, and I believe this is what is currently happening on my car. Yesterday I changed the oil to Mobil 1 synthetic 15w 50, as the thicker oil seems to leak less on my car, and maintains a higher oil pressure.

Not sure what you mean by oil leak....if you mean signs of oil in and around the oil filter/ turbo....Several places to check,if you are sure that the filter is tourqued correctly and you did smear the rubber casket with oil, and the matting surfaces were clean (no left over garbage from previous filter removal)...On turbo, check the oil feed and return lines, check return line at block as well, there is an "O" ring on the block side of the return line which may be shot; also the block side of the oil feed line (just to the left of the oil filter..about 11:00) may need to be tighten a bit.....On the other hand, if you mean that you notice blueish white (oil) smoke from the rear of your car, at highway speeds...and especially when you up-shift...the turbo oil seals are going (gone)..this I speak from current experience. Hope this helps you out....keep us posted...thanks..Al