Please advise me on how to replace transmission pan
seal on a 1997 GMC Sierra pick up automatic transmission. (1500 2 W/D) Thanks.
If you are going to do it yourself, be ready to have a mess on the garage floor.
The best way I have found is to remove the rear 4-6 bolts first. Then work your way toward the
front by removing 1 at a time from each side. When you get to the front 4-6 bolts, back them out
less than half-way so the fluid will start to run out the rear of the pan. Let fluid drain out rear for a
while, then hold your hand on the pan to position it back flush with the trans., then remove
remaining bolts and SLOWLY lower the pan. No real way to not spill.
Clean off magnet in the pan, clean off gasket mating surfaces on pan and trans., install new
gasket on pan and raise into position. Install a few bolts by hand so pan will stay up by itself, then
install remaining bolts.
1998 Chevy Astro. Engine size: 4.3L Vortec.
GM Computer codes: P0336
Question: Van was running fine, just finished replacing water pump and timing chain. Does not start.
Checked for fuel and spark. Does not appear to have both. Fuel pump sends pressure to injectors.
Tried quick start to confirm no spark. I have checked connector to crank position sensor several
times and for brakes in wire from terminals to 3 ft. away into harness. Is there any way to check if it is
the crank position sensor that is malfunctioning. I do not think there was any way it could have been
damaged through the timing chain replacement.
The cam and crank were not moved and remained in the same location as before. Is there anything
else I should check before replacing the CPS.($100) Any ideas that could help would be greatly
Answer: Well, the code P0336 is a Crankshaft Position Sensor performance code. I'd say you either
jarred the sensor during the timing chain job, or there is a wiring problem. Since it ran before the
work was done, it has to be something that happened during that time. It probably didn't have the
code before. If you're sure the wiring checks out, and the timing is where it should be, you're going
to have to replace the crank sensor and see if it starts then. It probably will, those sensors are very
susceptible to damage.
GMC Sierra Transmission Pan Replacement- Astro Van P0336