gear lube
 

I need to drain, clean, and refill my 4 speed transmission and Eaton rear end on a '67 C20. Do they use the same oil? Quantities?

Re: gear lube
 

Both should be 90wt. No clue on how much. My half ton diff takes about 1-1/2 quarts, car 4-speed takes about a quart.
The Eaton probably requires an additive.

Re: gear lube
 

My Dana 60 3/4 ton took over 4 quarts. Best bet is to buy a 5 gallon jug of Valvoline

As for your transmission, I'm pretty sure it needs Dexron. I used Valvoline Max Life Synthetic, and a bottle of Lucas tranny additive
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Re: gear lube
 

The transmission is 4 speed manual with very low ratio 1st gear.

Re: gear lube
 

He said 4-speed, so thats a manual if its original. Dexron is only for autos.

Re: gear lube
 

I have always used 90wt in manual transmissions and rear ends, at least up until the newer vehicles started using various other lubes.

Re: gear lube
 

Ah, ok. Gotcha
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Re: gear lube
 

i'd think if you bought a 5gallon jug you'd have at least 4gallons left over??? sounds like typical oil company logic there



me i'd just use royal purple fer everything // no additives needed

Re: gear lube
 

I meant to say I bought a 5 quart jug and used around 4 of it
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Re: gear lube
 

Download the factory manuals if you don't have them. The owner's handbook has a lot of good info there too. These will help you get on track with recommended service fluids and capacities.

http://67-72chevytrucks.com/vboard/s...d.php?t=558016

Re: gear lube
 

Thanks for the link. I wondered where those were.

Re: gear lube
 

I downloaded the manuals and they do specify 80 SAE at -10F and 90 SAE up to 100F and 140 SAE if the temp is consistently over 100F.

BUT the quantity is "level with fill plug" so we will only know after measuring what's left over.

Re: gear lube
 

Driver's handbook lists; 4-speed @ 8.0 pints, 5200# rear @ 6.5 pints

Re: gear lube
 

Thanks. That adds up to just under 2 gallons. I can get Valvoline in gallon jugs for $20 from O'Reilly, etc. There's a wholesale oil dealer not far from me and the smallest he sells is 5 gallons. I'll go see how much for a 5 Monday.