I have a question about my 1994 Toyota 4Runner. Briefly, I had the oil changed last week at Jiffy Lube, I had tires, new shocks replaced today. Today, I notice the temperature guage on the dash reading for first time ever. Oil level seems to be ok as does oil pressure. The tires are 1 size larger than stock, but that has been the case for past 60,000 miles (the redneck in me). I think I see a drop of oil on drain plug - perhaps slow leak? My first thought was something with the tires or shocks, but that makes no sense unless somehow the larger tires (32 x 11.5 as opposed to 31 x 10.5) caused excess resistance - not likely, especially since I've had these on. Could low oil cause this, or is it more likely to be the cooling system, a faulty temperature guage or a poorly reactive water cooler, or the water pump? Please help - of course it is Saturday & nothing is open tonight or tomorrow - so I get to think about it for more time than I'd like. Thanks for any advice!

 

Is your coolant low or leaking? Have you checked the overflow jug?

 

the monkey @ jiffey lube might not have tightened the drain plug all the way... could be low on oil making it run hotter, check the good ol' dipstick and see if it is up to level. If it isnt, take it back to jiffy lube, show em your receipt and tell them about the loose plug. They ought to tighten it up and top you off with oil. If oil level is fine, maybe check cooling system, but since there is oil on the plug i would check there first

 

Let me get this straight. Truck runs normal. Oil change at Monkey Lube. Truck runs hot. Coincidence?

Sounds like the "technicians" at Monkey Lube did not put the drain plug on right (not the first time) or they did not put a new drain plug gasket on. However, this would not be the cause of a high temperature unless it was REALLY low on oil. So, check the oil and check around underneath the vehicle. Can you park it in a "clean" spot? Check under the truck the next day and see if anything has leaked.

Let us know.

BTW: Exactly where is your temperature needle?