I plan on draining my trans today...what type of fluid and how much? Do I need to do anything else? Thanks!

 

From Novak:

When filling your T18 / T19 with gear oil, we recommend that you select a conventional mineral oil or a para-synthetic in lieu of a full synthetic oil. Properly assembled manual gearboxes do not have the thermal strains seen by combustion engines or hypoid gears. Synthetic fluid in these gearboxes, while not harmful, is probably an economic waste.

Hypoid gear oil is sulphurized higher than transmission oil and can be mildly corrosive to the non-ferrous alloys used for synchros, bushings and thrust washers in these transmissions.

An 80W-90, API-GL5 or MT-1 rated fluid is very good. Some claim faster shifts from using a 50W engine oil in their transmission and we do not consider this to be contraindicated unless you operate your vehicle in a very warm environment.

 

**Thanks!!

 

I thought they took Mercon.


Dcwright70

 

I was pretty sure they took gear oil, but I wasn't sure on the weight, etc. Gear oil is pretty damn expensive...$40+ per gallon for the name brand stuff...I ended-up going for the NAPA Brand for less then $15.

 

Mine looked like it had ATF in it though :?

 

My fluid is red and is ATF. I have been unable to find a reliable source that list what it was suppose to have in it.

 

That's apparently what the last owner did in mine...I've had it less then a year...you can find gear oil all day long at Napa, Autozone, Oreilly, etc...its just EXPENSIVE for the name brand stuff...but, like I said though...I went w/the Napa Brand Gear Oil for less then $15 per gallon. Can't beat that!

 

Does anyone know for sure on the amount of fluid...7-pints :?

 

All the manual trannies in these trucks (1980-up) took 80w gear oil or equivalent. That didn't change till the 5 speeds came out.

 

7 pints is what the manual says. I just fill it until it overflows the filler plug location; just pump it in

 

See my first post. Novak is a reliable source

 

I'm changing my clutch and have the top trans cover off. I figured this is a good time to change the trans fluid...if I can get the clutch done LOL

 

I'm wrapping-up my new clutch install....how exactly does the trans. top cover/shifter go back on :?

 

With a large screwdriver (or with the shifter, if it's still in place) flick the three selector forks in the lid into the neutral position.....so they all line up centrally in a row, when you look at them down through the shifter tower.

Then, in the trans, position the gears (including reverse) into their neutral positions & carefully slip the cover back on, guiding the forks into the correct grooves. This might work on the first try, or it might take a few attempts........just take your time.

Put a couple of bolts into the lid & try selecting each gear (again including reverse) before you bolt it up fully.

Be careful not to let the 1/4" pin that engages into the shifter (through the side of the shifter tower, under the cap) drop down into the trans as you re-assemble it.