MO-Runner

Due to problems at the dealership have recently started doing my own oil/lube services. Now, am going to make the jump to synthetic. After reading up and searching the various posts here I have decided on Mobil 1. (Primarily due to the ease of finding it.) This leads to my 2 questions.

1. Can not find straight 90w gear oil in Mobil 1. My manual says 90w or if below 0, then 80-90w. However, all I have found is 75-90w. Problem?

2. According to the posts I have read about flushing the transmission, I am sure there will still be some old ATF left in the system. Will this be a problem if it is mixed with the Mobil 1 ATF? Label says compatable with regular, but have heard it can cause foaming if enough of the old is left mixed in. I believe this is a claim with the oil/gear oil as well. Truth or Myth?

Thanks,
db

bktaco

the steralorship here uses 75-90w. hope that helps.

Ilovemountains

Hi, I switched over to full synthetics about 40,000 miles ago. I did the switch in my engine first. I changed the oil over to Mobile 1 10w30 and ran it for about 2500 miles then changed it again with the same. I then let it go to 4,000 between changes. My 3.0 sounds better, starts better and has more oil pressure at start up than it had with regular oil. I have not had any problems and my engine is a 1988 with with almost 150,000 miles on it!... I did have the valve cover gaskets and cam seals done before I switched since they were starting to leak a little. It is a known fact that synthetics DO NOT make leaks but if there is a pre existing leak or seep the synthetics can find their way through them easier than dino oil. I always run either Purolator Pure 1 filters or Toyota also, no Fram crap.. I ran Bosch filters for a long time thinking they are really superior to others but I was wrong. I read an oil filter comparison like this one that made me switch over http://www.frankhunt.com/FRANK/corve...lterstudy.html . As for my ATF I change it every 25,000 miles. I always used Quaker State "special import formula" until one day I could not find it and didn’t feel up to going into my least favorite place, Wal Mart, or Wally world or hell....to find it so I bought some DexronIII AAmco stuff at Auto Zone. Well when I changed it I also did the filter, " I only check it every 3rd change since it has yet to even be dirty"! When I got finished my truck shifted fine up but wouldn’t go back into 1st, like when you would slow down for a speed bump, you could hit the gas and it would just rev, like it was in N so I drained it out again and switched to Mobile 1 full synthetic. Now it shifts like new, sounds much better and best of all before my OD wouldn’t even come on till I was miles away from home I guess it had to warm up, with the synthetic it is not affected by cold temps so my OD shifts right in like it should. Just my early Monday morning .02 switch to synthetics your truck will thank you at about 300,000 miles

Ilovemountains

I also switched both of my diffs over to 75/90 M1 last year. I got stuck and blew one of my rear tires. I installed my spare which was a few sizes smaller than what I had on at the time and drove home. It never occurred to me to put it on the front and put the larger tire on the rear "I have manual hubs". So by the time my replacement tire came in, hail to Costco’s road hazard warranty I had done some internal damage to my rear end. I switched to full synthetic and it made cut the noise in half. Im not sure if it was the synthetics that did it, or just the fresh fluid. Now on another note.. My 2000 Triumph Sprint STs engine went bad, well really the transmission and it was the fault of a bad chain break. In stead of repairing the broken case that had nearly 40,000 miles on it I found a used LOOOW mile used engine. I decided that I was going to take my old one apart just to see how much wear was in there. Triumphs use Mobile 1 Racing 4T oil from the factory and I have always used it. According to factory specs there was NO wear. The only wear I found was on the shift fork tips and the shift drum/dog assemblies but that’s from MANY hard shifts and a lot of 2 up loaded touring! Anyway I’m sold on synthetics, its already a “Monday” and I’m typing away from the office like some type of coffee coma induced drone… happy Monday every one..

2001Millrunner

I do my flushing at Jiffylube because they have the T-tech system that actually passes 16gal?qt? of fluid for complete flush. I notice smoother shifts after this is done. If you're weary about mixing fluid then you can buy your own ATF and have Jiffy lube do it too. I just have them use their ATF because it can get expensive when you have to buy your own. They charge about $80-$90 if my memory serves me right.

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I'm going to switch to Synthetic after my second oil change. Right now i'm using Castrol GTX dyno while engine breaks in. Not sure though if I want jiffy-lube work on my truck (bad experience in the past). There are few here in KC that will charge you extra for a drop of winshield washer, also disconect everyfrigging thing and leave it hanging. Do it right--DIY...

MO-Runner

Thanks much for the info. Looks like I will go ahead with doing the engine, diffs and transfer case myself, but may take my own ATF to a shop and have them flush with my own fluids while I am there. That way will not have to worry about leaving some of the old in. Don't really like having to pay that much, but might be worth it to avoid the worry. I plan on running about 500 miles or so and re-doing the engine, diffs and transfer case to make sure is all synthetic.

Thanks again for the feedback!
db

Cebby

I bought a case of Royal Purple today and will be changing over this weekend. I have a little oil on the back driver side of the engine, but I think I just need to tighten my valve cover a little or possible change the gaskets.

Anyone running a remote single filter with synth?

Ilovemountains

Cebby, my dads 02 TRD Taco has a remote filter installed. I do not like where he put it but his idea of off road is off pavement onto gravel or grass! He mounted it in front of his driver’s side front wheel! All road spray and flying objects from the highway hit the damn filter. The other thing is he swears by Fram filter “they used to be the best you could buy" blah blah blah. At least I got him to run synthetic oil! As for changing it and running 500 miles then changing it again that’s a waste of $$, all synthetics are made to mix 100% with dino oil. I’m not saying that I would leave it in there for 5000 miles mixing through but I’m sure you could if you want to, 500 miles is a waste of good synthetics! I would run the engine 2500 miles then change it out and the Trans a good 10,000 or so. As for the diffs, they could go a solid 20,000 or more! My truck ran the original diff fluid for 90,000 miles given it looked like silver paint with the consistency of very thin motor oil when I did change it but that was after my large tire, small spare incident! Just my thoughts, as for the filter relocation kit, I am totally against installing it in the wheel well! I wanted to install one on my 3.0 and pipe in an inline cooler but there is no where to mount the filter, that I can see any way! Have a good one, Matt

Cebby

I've been doing some digging on these relo kits. It does not appear that I can use a genuine Toyota filter (which I just bought). I think I can reach in through the wheelwell to get at it though.

I was reading Royal Purple's site and they said that the synth is 100% compatible with dino and that no special measures need to be taken when switching over (like flushing).