Toyota tacoma rear differential breather kit and water in the gear oil

dlogvine

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I know it might be the wrong forum but it is related to the boating and water so I will post the question here, if not, I'll try to find some toyota trucking forum and ask it there. After taking my boat to the lake I noticed some oily drops under my rear differential of my 2015 Toyota Tacoma trd off road. I looked inside and realized that gear oil was al messed up and mixed with water, so that it looked like mud than oil. I found out that a breather was a small hollow bolt with cap on the top of differential instead of an extended hose with some one way valve like I had on my previous truck. Talking about off road Tacoma!!! What a joke. Since the cap was just a little bit over the rear differential the water was getting inside almost every time I was taking the boat in or out of the water.
So I have two questions, first is the following,
Is there any place I can get an extension for a breather valve kit?
Second, I change the gear oil immediately, tried to clean up the gearbox with brake cleaning fluid, but I believe this muddy oil that was in the differential for a while needs a lot better cleaning than that. So I'm going to drive the truck for a weak, allow the new oil to get into the bearings and all gears and than change the rear differential oil again. Shall or can I use some cleaning addend to better clean the bearings and gears? Im thinking about using some marvel oil and running the truck for 30 minutes to let it soak all the gears and than change gear oil. Any other ideas? Thank you and apologise for posting truck questions in the boating forum.
Thank you again, any help is greatly appreciated.
 

alldodge

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I think what your doing is fine, I wouldn't add anything else other then the gear lube.

My 2500 ram uses synthetic transmission fluid in the differentials. Kind of caught me doing a double take when doing a change the first time
 

dlogvine

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I think what your doing is fine, I wouldn't add anything else other then the gear lube.

My 2500 ram uses synthetic transmission fluid in the differentials. Kind of caught me doing a double take when doing a change the first time

I put synthetic 75W90 in the rear differential, I think originally toyota uses conventional gear oil. But I found an extension kit that lifts the breather up, suggested places for the valve are either the gas filling cap location or the rear light location, will have to look at which one is a better fit.
Anyways, I was very surprised that off road truck would have a breather valve so low on a differential that the water gets in any time the truck gets at least half wheel deep in the water
 

Bob_VT

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Look on ebay and they sell them with a long tube. You might want to call toyota about it too
 

alldodge

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Anyways, I was very surprised that off road truck would have a breather valve so low on a differential that the water gets in any time the truck gets at least half wheel deep in the water

Guess it depends on how you look at off road. Is it rocks, dirt, mud and weeds, or swamps, creeks and ponds. I would look at the latter as a swamp buggy. In any case you caught it before there was damage
 

MTboatguy

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Low breathers are pretty common, because believe it or not not all that many guys actually use the trucks off road. I think last article I read on off road use said around 15% of trucks and SUV actually ever get off the pavement. That said, the first thing I check when I buy a new truck is the breather systems. As far as the rear end, normally it takes quite a while running them with a water/grease mix before you do damage to them, I would probably do what you did, drain, brake cleaner, refill, drive for a week or so, then drain, brake clean and fill with your choice of gear oil that meets the manufactures specifications.

Good luck.
 

Scott Danforth

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most people that own 4x4s dont even go over a curb to the back yard, so why would Toyota waste money. those that go fording do a snorkel kit for the motor and do remote breathers on the diffs, T-case and transmissions

while you are adding a remote breather to your rear diff, you may want to add one to your T-case, trans and front diff.

I normally extend my breathers up to the fire wall. Just watch the loop on the rear axle so you dont pull it loose when the axle drops, then snag it :facepalm:
 
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