The 40. 1997 Jeep Wrangler needs 6 quarts of oil for an oil change.
I have a 1991 a 1992 and a 1993 jeep wranglers and all take 6 quarts of oilwith a new filter installed. I use 10-40 weight oil in all mine its good for all yearand all weather driving. Be sure to change every 3,000 to 4,000 miles if you loveyour jeep like I do. Jeep people are the coolest but you have to not have aproblem with getting it dirty. Jeeps like dirt and mud.
40 Psi
WD-40
35 to 40 psi
I put 10 w 40 in my 97 4.0 liter wrangler now it sounds diffrent. I think it should have had 10 w30 . Manual calls for 10w30
a little WD 40 should do the trick
Just the opposite, 30 weight oil is thinner that 40 weight oil and will flow better at low temperatures.
That means the oil is 15 weight when cold and 40 weight when hot. The higher the number the thicker the oil.
This is a tricky question but simple at the same time. 15w-40 oil is never a 40 weight. As you know oil thins as it heats up. What the 15w-40 designation means is that the oil starts out at 15 weight but thins out like a 40 weight as it gets hot (i.e. it stays thicker for a longer period of time). If i could draw you a graph you could see this much plainer. A 5w-30 oil starts out as 5 weight but thins like a 30 weight. Does that make sense?
10w/40
Jeep Wrangler takes 6 qts. Jeep Cherokee takes 6 qts. The oil pans are fairly large on these vehicles. Additionally for those who need the proper viscosity information, it is as follows (directly from the maintenance manual): Above 30 degrees F ..... SAE 20W-40 or 20W-50 Above 0 degrees F: SAE 10W-30 or 10W-40 Below 60 degrees F: SAE 5W-30