oil recommendation for 1948 Chevrolet Fleetmaster club sport coupe

Joined
Nov 10, 2014
Messages
176
Location
Colorado
My sister-in-law has a 1948 Chevy Fleetmaster 2 door coupe with a 214 ci inline six and three on the tree. The odometer has 99,500 miles on it but who knows if it's double that or even more. It's in very good condition for its age (both exterior and interior), but naturally has a number of mechanical issues (pan gasket leak and maybe a rear main seal leak). I spent a weekend in Kansas cleaning it up (it was left in a metal barn for a few years as her husband was ill, unable to care for it, and passed away last year). Luckily no critter damage.
I have no idea when it had its last oil change and grease job so that's next on the to do list. The "original" owners manual says 10w under 32 degrees, 30w over 90 degrees and 20w for everything in between. I was thinking of using a high mileage 10w30 conventional oil but thought I'd bounce that idea off the community. I have no experience with these antiques and don't want to cause any potential damage. Our hope is to take it to a upcoming local car show and advertise it for sale.
Some interesting info about the car...about 54,000 of this model were built and it is one of about 340 known to still exist. It was considered a 2 door sports car for its time (yea right!) and has a whooping 90 hp!!! I drove it around her little western Kansas town and it sure attracts a lot of attention. It drives and handles like a tank (weighs approx 2.5 tons and feels a lot more!) and is really slow. That hood seems to be a mile out in front of you and visibility in general just s__ks.
 
Valvoline VR1 10W30 is now at Walmart in 5 quart jugs.

That is what I would use, although your plan is fine.

Rear main seal is a rope seal, kind of a pain to replace. If the leak isn’t too bad, I would live with it.

Sure its not a 216?
 
Use a little snake oil in the fuel like mmo or a small dose of 2 cycle to keep your valves going.

Any oil from HD20 to 10w50 depending on how much it eats

10w30 is a good year round oil

Synthetic is a good choice if it’s not going to get driven a lot or has mechanical issues/oil dillusion
 
One more thing, check the fluid in the transmission and make sure its full. The ujoint is lubed by that oil.

If transmission oil level is low, check the level in the rear end. If that level is high (and transmission oil was low), then you likely have a driveshaft seal leak.

Just keep this in mind before driving it much more.
 
One more thing, check the fluid in the transmission and make sure its full. The ujoint is lubed by that oil.

If transmission oil level is low, check the level in the rear end. If that level is high (and transmission oil was low), then you likely have a driveshaft seal leak.

Just keep this in mind before driving it much more.
Thanks for the recommendations. I will check those areas you suggested. As I said, I know so little about these older cars. I rode in them alot as a child (I'm an old poop) but I wasn't very impressionable at the time.
 
hopefully this worked picture wise. edit ......Sorry it didn't..... keep getting a "oops sorry we have problems message"...... clearly I'm the problem.
 
Last edited:
  • Haha
Reactions: SR5
My father and brother generally run whatever 10w30 they have on hand in their antiques. Mostly Plymouths with an L-head 6 or a slant 6. (They have several of each)
 
PXL_20240527_194715304.jpg
 
Here's what I use in a 1952 Chevy DeLuxe, Shell Rotella T4. This oil comes in two different weights, I use the 10w-30 version.

1717010111729.jpg
 
Not clear in the picture, but the roof is a dark brown/deep bronze color. Nice color contrast with the green.
 
Valvoline VR1 10W30 is now at Walmart in 5 quart jugs.

That is what I would use, although your plan is fine.

Rear main seal is a rope seal, kind of a pain to replace. If the leak isn’t too bad, I would live with it.

Sure its not a 216?
You're correct, it is a 216 ci. my bad.
 
Back
Top