80w-90 gear oil will work best for this transmission.
There are several versions of the Muncie 4 Speed, Muncie M21 & M22 the SM465's and the SM420's. The SM465's for example were used in 1968-1991 General Motor Trucks Fluid Capacities should be in the 8.4 pints area from what I can find. Hope This Helps.
Saginaw-Muncie 465, used in GM light duty trucks until 1987. Four speed manual transmission, direct drive. Very solid, reliable transmission.
80-90wt gear oil GL-4
To check the fluid level in a Muncie 4-speed transmission, start by locating the fill plug on the side of the transmission case. Remove the fill plug using a wrench; the fluid level should be just below the fill hole. If fluid drips out when the plug is removed, the level is adequate. If not, add the appropriate type of transmission fluid until it reaches the desired level.
The transmission fluid needed for the 1989 Chevrolet K1500 with a manual transmission is Synthetic Synchromesh transmission fluid (5W-30) (MTFQT). If the transmission you have is the MG5 5-speed, the capacity is 4.2 pints. If the transmission is the SM465/M20, the capacity is 8.5 pints.
mine holds 2.5 quarts so that is my answer.
The address of the Muncie Children'S Museum is: , Muncie, IN 47308
Chuck Muncie's birth name is Harry Vance Muncie.
The address of the Muncie-Center Township Public Library is: 2005 South High Street, Muncie, 47302 4073
Chuck Muncie is 6' 2".
Muncie Flyers ended in 1925.
Muncie Flyers was created in 1905.