Cold weather oil in L-134 -
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back > Models > Jeep CJ Forum > Cold weather oil in L-134

JKS Grand Cherokee WJ, Adjustable Front Trackbar 1"-6Teraflex JK HD Hinged Carrier & Adjustable Spare Tire FREE, FREE, FREE EVENT!! Save big on Lockers now till Apri

Unread 12-21-2008, 09:15 PM   #1
Registered User
1949 CJ3A 
Join Date: Jun 2008
Location: Edmonton, AB
Posts: 83
Cold weather oil in L-134

What oil would you use in a 1949-ish L-134 flathead engine, when the outside temperature is -30C (-22F)?

I tried to start the Jeep today in those temperatures, but the battery was toast so nothing happened at all when I pressed the starter button...

But since there was no block heater on, I don't know what would have happened if I had been able to turn it over. I haven't changed the oil since I got it in the summer (I doubt it's gone 20 miles in that time), so I don't even know what's in there right now. But the PO lived in warmer climes--rarely dropping below -10C (+14F).

I put a battery warmer on it, and next time I go out to the acreage, I'll bring along a battery charger. Between those, I should be able to turn the engine over. But I should probably put some light weight oil in it, too. What rating would you suggest? I know that modern cars say to use 5W30 all year, and that seems to work fine in all newer cars I've owned, but a flathead is a different beast!


PaulS is offline   Reply With Quote Quick reply to this message
Unread 12-21-2008, 10:24 PM   #2
Ridin' Around
Registered User
1999 WJ 
Join Date: Dec 2007
Location: Rochester, Illinois
Posts: 2,210
Paul, I would suggest looking at Amsoil's HDD 5W-30. It is listed in their diesel oil category but has a high level of ZDDP additives that the flat head will like and be good through the warmer weather. A second option would be the AMO 10W-40, it is also a high ZDDP oil and will go a little heavier in weight while remaining a highly flowable oil in the cold. The pour point is -44*c. Hope that helps.
Ridin' Around is offline   Reply With Quote Quick reply to this message

Quick Reply

Register Now

In order to be able to post messages on the forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools

Suggested Threads

Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. is not in any way associated with Jeep or the Chrysler Corp.