Ready or not, here I come. (1 Viewer)

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Matador98

SILVER Star
Joined
Aug 11, 2004
Threads
19
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473
Location
Santa Maria, CA
Website
www.esaero.com
Hey guys, I'll be joining this side of the forum very soon. I just bought my pregnant wife a '99 100 series to be her "new" grocery getter (and it'll see the Pismo dunes every once in a while). Anyways, I'ved owned a 60 since may of 2000, and am stoked to now be a two cruiser family.

This 100 has a load of miles on it, 192K to be exact. I don't know the service history up to 150K, but after that it was owned by a Toyota technician, and he sold it to the current owner at 185K. I know it's been dealer maintained since 150K. And no, the timing belt (a second time) has not been done. It is first on my list.

However, do you guys think it is too late for me to convert to synthetic fluids. Oil, tranny, transfer, and diffs? The underside of the truck is dry as a bone and does not currently leak. I am of the belief that age will affect the ability to convert to synthetic and the possibility for leaks more than miles. So as of now, I am leaning towards converting all of the fluids to synthetic soon after I pick up the rig (this week). Also, what about using detergents at this high mileage? I'm leaning towards not. Searching, I see a difference of opinion on the tranny. Should I use synthetic at all, and regardless of that, should I drain/refill or do a complete fluid exchange. I don't now when it was last done.

What do you guys think? Do you think I would be taking a risk converting, or am I good to go? If I do convert, I think it will freshen everything up and add that much more longevity to the life of this truck.
 
Stick with whatever type of oil has been used up to this point.
 
I switched my 80 to synthetic at 124K miles and never got a single leak. Just a data point. Some have reported that you might get initial leaks, but they will seal up after a while. Check the archives.
 
It's and old wifes tale. There is no problem with changing at this point. Do note the 100 is very easy on oil.
 
You can check this thread for some discussions on high mileage vehicles.
 
All the oils are going to to be high detergency and could dislodge theorectical acumulated crud if there was some (not likely to be any). Synthetics are formulated with seal conditioners just like other oils. So I see no problem. I'm not even sure 192k on the UZJ is "High milage".

I also see no real need but if it makes you feel good then go for it (it makes me feel good ;) ). As far as synthetics go I think you get more bang for the buck in the Diffs and trannies because they have long OCIs and no combustion contaminants.

For the transmission, How I would procede would depend on the condition of the fluid. If it looks good and fresh then drain and fill. If it looks bad then exchange or Drop pan and exchange. Also if you are going with a high dollar synthetic product then a complete exchange will get you to ~100% fluid cheaper than drain/fill.

Don't forget new brake fluid. Probably the most important and the one most likely neglected.

Stick with whatever type of oil has been used up to this point.

I don't see the logic in this idea. What if that means garage sale oil and supertech filters with haphazard maintnence. The truck is not a creature of habit that will resist a new better way of doing things.
 
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Thanks for the input, guys.

During my check, the tranny fluid looked pretty good, but I don't have a service record of when it was done. Maybe I'll try to ease it into synthetic, do a couple of drain and refills, and then a full exchange in 5-10K or so. Does the 100 series have a transmission filter, or is it a metal screen, like the Tundra?

Sounds like I don't need any detergents at this point, and I think I agree with that, even in the engine. There should be no sludge or buildup.

Thanks KathmanduCruiser, I already found that post and bookmarked it. It just didn't seriously address synthetic conversions.

cary, I did notice that it was easy on oil. When I checked it, his service records showed it had 4K on the oil, and it looked brand new. My tundra is the same way (and it's virtually the same engine, so no surprise).

This is a good thread so far guys, I'm getting lots of good feedback, but for the guys that aren't for it, like justimaginejack and spressomon, why not? Seems that there is a lot more support for changing the fluids out rather than not, so I'd like to hear it. Also, it'd be good for the sake of others in the future when they do a search for this as 100s get higher miles on them and they become cheaper.
 
Oh, and as a another data point, or two, I helped my friend convert his 1999 5.7L Yukon to full synthetic at 115K 9 months ago, and my other friend convert his 1996 4banger Ford Ranger (engine oil only) 1 year ago, and both of those domestics were perfectly fine. That's another reason I think this UZJ would be good to go.
 
Listen, I did it and ended up replacing a radiator with a minor leak, that became more so. I am actually glad, I caught it before it blew up on me. I know the women who did the first 99k miles took it to toyota religiously every 3k and changed the oil. They never did anything else because the fluids looked "ok."
The differentials were pretty messy, but the Truck still runs. Upgrade it, just don't do it when you are about to leave for a trip. Keep it around for a while and check for leaks.

As for the motor oil, Mobile 1 makes an oil for just this, if you have a high mileage car, and want to switch to synthetic, or not sure what the previous owner ran, then use Moble Clean, it should help protect and clean seals.
http://www.mobiloil.com/USA-English/MotorOil/Oils/Mobil_Clean_High_Mileage.aspx

I would love to protect all of us from the inevitable, but I guess it would not be inevitable. Just do it, make sure you have some cash set aside for repairs and enjoy fixing it.

I did get better mileage after doing the updates, but I did everything. Spark plugs, belts, fluids, tires, brakes, everything. It drove like a different vehilce, except for the over heating part. But I got that fixed within a week of the whole work over.

Best of Luck, let me know how it goes?
 
All the oils are going to to be high detergency and could dislodge theorectical acumulated crud if there was some (not likely to be any). Synthetics are formulated with seal conditioners just like other oils. So I see no problem. I'm not even sure 192k on the UZJ is "High milage".

I also see no real need but if it makes you feel good then go for it (it makes me feel good ;) ). As far as synthetics go I think you get more bang for the buck in the Diffs and trannies because they have long OCIs and no combustion contaminants.

For the transmission, How I would procede would depend on the condition of the fluid. If it looks good and fresh then drain and fill. If it looks bad then exchange or Drop pan and exchange. Also if you are going with a high dollar synthetic product then a complete exchange will get you to ~100% fluid cheaper than drain/fill.

Don't forget new brake fluid. Probably the most important and the one most likely neglected.



I don't see the logic in this idea. What if that means garage sale oil and supertech filters with haphazard maintnence. The truck is not a creature of habit that will resist a new better way of doing things.


#1) Back in the day it was recommended to me to stick with the same brand of oil for best performance. Short of knowing that then I guess it doesn't matter.

#2) He stated it's going to be a "grocery getter"; typically this means little time running hot for any extended period. Changing the oil more frequently is a better strategy; maybe as often as every month/every other month when a vehicle is driven for short durations where contamination from diluted oil (from not running for extended periods of time to keep the engine hot) is more the concern (dependent to upon climate conditions where the vehicle is driven).

#3) The most critical part of an engine's life is the first half (really the first 25k) not necessarily the last half. If this rig did not see frequent maintenance (crankcase oil, diffs, etc.) it's going to be pretty difficult to make up for lost time...even with synthetics.

#4) Even though I run syn in all cavities of my 100 it is a fact syn is best for extreme temp and/or extreme duty conditions/usage...but hey it's your dough...spend it as you wish.

#5) I did have seal issues with a Saab 9000 that I started running syn in at 80k...mechanic told me it was caused by the syn oil.

As far as diffs/t-cases go...they do not have any filtration. Again in extreme applications syn might just be worth the extra expense but NOT at the expense of refresh intervals...expecially in diffs & t-cases where, again, you have no filtration: Ever drain a diff yourself and take a peak at the metalic content that comes out with the oil?

Eveyone has their $.02...I just added mine.
 
matador, what type of oil/filter do you run in the tundra? What has been your service history on that? They are the same motor, so go with what you have been doing in that motor.
 
Eveyone has their $.02...I just added mine.

And thanks for it. I'm listening.

1loudLX, I use Mobil 1 in everything and use either purolator pure one's or Napa Golds on the engine. Oil every 10K, Diffs 30K, tranny drain and refill every 30K. That is probably what I would do with this UZJ, but I'm still on the fence.

Any others?
 
FWIW, I submit that issues with seals leaking upon changeover to synthetic, are related to the seals themselves - design, materials, & mfg quality of all elements of seal, including elastomer element and mating components.

How many people have had problems with Toyota seals leaking, upon changeover to synthetic oil? (Not me)

I did have a 96 GMC pickup that developed a leaking rear main seal upon changing to synthetic. But that was not a Toyota. For reference, look at various in-service vehicles built in the last, say, 20 years, by different manufacturers. A vehicle built by one of "The Three" will have multiple fluid leaks in any case - but a Toyota or other well-made vehicle will have virtually no fluid leaks, even to high mileage. It's a different philosophy - "The Three" accept small leaks as OK, as long as the sales & profit$ are not impacted, so seals that start leaking after warranty expiration are accepted. But Toyota designs & builds seals to fully SEAL.

(And I've found that people who accept general vehicle quality of "The Three" also typically accept leaky seals on their vehicles as "normal".)

See for yourself.

(Of course, leaky seals and other things of inferior quality are what finally led to the current demise of "The Three". I value leak-free seals - don't you? There are numerous other examples like this, when comparing vehicles by different marques.)
 
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Tinkerer, i dont even know you you can call something a leaky seal...because if its leaking, ITS NOT A SEAL, lol.
 
Tinkerer, i dont even know you you can call something a leaky seal...because if its leaking, ITS NOT A SEAL, lol.

Good point!

And I agree with most of spessomon's $.02.

#1 - Mute point as it probably got whatever the PO's mechanic had on hand that day (and that was probably fine).

#2 - Agree - short trips where the oil never get to temp indicate short OCIs for the engine.

#3 - Don't know but doesn't sound unreasonable. And agree you can't make up for past wear.

#4 - Supertech oil and a Toyota filter at factory intervals will probably keep a 100 going for a longer time then most will be in service.

#5 - I would have thought Swedish cars more synth freindly given their temp extremes but have no experience. Saab is however owned by GM which is notorius for horrible leaking "gaskets". I still have oil absorber left from when I owned GM cars. Haven't used it at all since I went all Toyota.
 
Tinkerer, i dont even know you you can call something a leaky seal...because if its leaking, ITS NOT A SEAL, lol.

Actually, on a molecular level, most seals leak. In fact, very few seals actually completely seal, when you get right down to it. And some seals are more leaky than others, by design - for exa., so-called labyrinth seals, that do not use an elastomer sealing element at all.

But in a given class of seals - e.g., elastomer wiping/lip seals - those made by manufacturers like Toyota typically perform much better, with virtually zero leakage for >100k miles, compared to those fosted on consumers by The Three. (Now, of course, the seal design includes more than just the wiping element per se...)

;)
 
Actually, on a molecular level, most seals leak. In fact, very few seals actually completely seal, when you get right down to it.

Water pump shaft seals are no different. A small amount of anti-freeze residue at the weep hole when the time belt is changed is normal, not a sign the shaft seal is about to fail.
 
Water pump shaft seals are no different. A small amount of anti-freeze residue at the weep hole when the time belt is changed is normal, not a sign the shaft seal is about to fail.

I agree - enough so that I left my Water Pump in place when I replaced the timing belt at 89k. Pump had slight dried residue at weep hole.

Pump still doing OK, at 105k. We'll see. :)

(But also: Pump/seal life is probably affected by coolant condition, over service life. It will likely last longer if coolant changed every 30k, using distilled water in refill mix.)
 
So matador, is the 100 in the driveway or not? If so, add it to your signature and PLEASEEE post pics!
 

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