94 4runner 5w-30 vs. 10w-30?

[ozzyleven]

I am trying to decide which type of oil I should run in my 1994, 172,xxx miles on it. I have been told by the local Toyota mechanic in town that I should run 5w-30 engine oil in it, previous owner used 5w-30 Penzoil, but right on the cap, it recommends 10w-30. I live in western Montana and its pretty cool here for the majority of the year, actually very cold for most of it. Problem is that for about 2-3 weeks each August it gets up around 100+F and is around 70 or so through June-July. Is it going to cause problems for the engine in the summertime or will it be okay?

On another note, the Chilton's guide recommends oil changes every 7,000!? That just sounds crazy to me. I'm used to oil changes every 3000. When do most of you change out your oil? Trying to get the most out of this ride, since I'm already getting pretty attached to it. Thanks for your help!

 

[Climb14er]

I had V6 1993 Pickup 4 x 4 and always used 10W-30 Synthetic. Started up in the coldest Colorado winters and did well in the scorching summer heat.

Personally, and of course, you can use what you want... I think the 5W-30, which is what I now use also in synthetic for the 2007 4Runner is too thin for the wider tolerance engine of the late 1980's design and early 90's build.

 

[KB084RUNNER]

I always follow the manufacturers suggestion. If you are concerned about cold temps use a 10w30 synthetic which pumps to -30F. So, unless you live on the moon you will be fine. Pennzoil Platinum will do fine in that rig. I change every 5000 miles.

 

[Toyodas]

If it were mine I would do several short 3,000 miles/3 months oil change intervals including oil filter change and run it hard during that time.

My oil of choice would be any current API SN conventional or semi-synthetic blend high mileage 5W-30 during at least two of those short intervals. During this time I would check oil color (blotter test) every fill-up and also look around the engine bay for any NEW oil leaks. After two short intervals and everything looks good I would increase the oil change interval.

If you plan on keeping your '94 for another 170,000 miles and feel the need for a full synthetic 5W-30 be cautious about valve cover gasket leaks caused by the full synthetic cleaning already gummed up gaskets from years of conventional oil use. If this happens I would consider having the valve cover gaskets replaced along with all the other gaskets that are on the valve cover housing, intake plenum, throttle body, PCV valve grommet, etc.

Our 1997 Limited 4Runner 2WD w/ the 5VZ-FE V6 has nearly 200,000 miles on it and the latter half of those miles I used either semi-synthetic or full synthetic 5W30 or 0W-30. At 175,000 miles, the seepage of motor oil around the valve cover gasket became progressively worse so I had all upper gaskets replaced.

If all goes well, I'm looking forward to another 200,000 miles or more.

 

[RS Dude]

If it were mine I would do several short 3,000 miles/3 months oil change intervals including oil filter change and run it hard during that time.

My oil of choice would be any current API SN conventional or semi-synthetic blend high mileage 5W-30 during at least two of those short intervals. During this time I would check oil color (blotter test) every fill-up and also look around the engine bay for any NEW oil leaks. After two short intervals and everything looks good I would increase the oil change interval.

If you plan on keeping your '94 for another 170,000 miles and feel the need for a full synthetic 5W-30 be cautious about valve cover gasket leaks caused by the full synthetic cleaning already gummed up gaskets from years of conventional oil use. If this happens I would consider having the valve cover gaskets replaced along with all the other gaskets that are on the valve cover housing, intake plenum, throttle body, PCV valve grommet, etc.

Our 1997 Limited 4Runner 2WD w/ the 5VZ-FE V6 has nearly 200,000 miles on it and the latter half of those miles I used either semi-synthetic or full synthetic 5W30 or 0W-30. At 175,000 miles, the seepage of motor oil around the valve cover gasket became progressively worse so I had all upper gaskets replaced.

If all goes well, I'm looking forward to another 200,000 miles or more.

Regarding the leaking valve cover gasket...mine started leaking also after I went to full syth...but thought is was because I had reused the gasket from the previous 30k tune-up.:naughty:

 

[ozzyleven]

I ended up putting Castrol GTX (any thoughts on quality?) 5w-30 in it, partly motivated by the fact that it was on sale. I now feel like the oil pressure is lower on it than it was before. When its at an idle the pressure is a little under the quarter mark and a little under half when accelerating. It used to be above half when accelerating, closer to 3/4. I know for sure the previous owner was using Penzoil 5w-30 because he left bunches of crumpled up receipts for it in the glove box. Would a change in brand produce that much change in pressure? And are the current pressure levels anything to worry about? If it helps, the old oil actually looked pretty clean. It seems regular oil changes were the only thing the previous owner actually ever kept up on.