Servicing of a 2003 Tacoma transmission

In 09 I gave my dad a 2003 Tacoma. He says it has ran well for the past years, but recently has complained that he thinks the transmission is going out. Obvious question I asked him if he had gotten the transmission fluid serviced? His reply was that the transmission and the engine shared the same fluid so changing the engine oil services the transmission. This sounds crazy wrong to me, but I don't want to argue with him if he's right somehow. Can someone please set me straight?

EDIT: If it matters for context, I live about 26 hours away from Dad, this conversation was all over the phone.

 

Totally different systems and fluids. Early English cars shared fluids in a common case. nothing modern does afaik

 

Um...yeah, your dad is wrong. The transmission and engine are two separate units. Both have their own respective (and different types) of fluid.

Is it an auto trans or a manual? Manuals for these trucks take 75w90 gear oil. Automatics take ATF (automatic transmission fluid), Toyota makes their own brand I believe and it's recommended to use that.

The engine takes engine oil, 5w30 standard unless it was switched to synthetic at some point.

 

My 1967 Mini Cooper s shares the same fluid as the trans and the engine

My 01 Tacoma certainly does not

 

Thanks for giving serious answers. I'll talk with Dad tomorrow.

 

Manual transmission. He says he's changing the engine oil regularly. His statement on the transmission oil threw me. I just sort of stood there holding the phone, it sounded so wrong, and yet he sounded so sure of himself and I didn't know absolutely for sure.

 

Well, in your dad's defense (and I wasn't aware of this myself), it sounds like on some much older vehicles the engine and transmissions DID in fact share the same fluid, so it's not that far fetched for him to assume that.

The good news is, the manual transmission is a very simple and strong design (compared to the auto) and it's tough as nails...you'd have to try pretty hard to 'ruin' it. It would definitely be a good idea to drain/fill the fluid ASAP if it's not acting normally and hasn't been serviced in a long time.

There are a few highly recommended brands out there, Redline 75w90 is probably the most popular as it seems to help smooth out harsh shifting. Royal Purple and Valvoline are also reputable brands.

 

Also, it's really easy to do yourself. I don't have a garage or much mechanical experience at all but I can change out the fluid in my manual trans myself in under 20 minutes. Make sure the truck is on a level surface. You have a fill plug and a drain plug on the trans. Crawl under the truck and loosen the fill plug first (so you know for sure that you can fill it after it's drained), then loosen the drain plug and let the old gear oil drain out. It's recommended to use new crush washers for the fill/drain plugs when you put them back on, they're like 10 cents each from Toyota or Amazon.

Tighten the drain plug back on, then fill the transmission up through the fill port until you see fluid start to drip out. That's when you know it's full. Put a new crush washer on the bolt, tighten it up and you're good to go.

 

Actually I assumed your truck was a 6 lug (4x4), if its a 5 lug 2wd be sure to check the manual to see what kind of weight the gear oil needs to be for the transmission, it might not be 75w90 like the 6 luggers use

 

Some 35-40 years ago Dad did work on cars to some degree, so maybe this is where the idea came from.

If it hasn't been changed since 08 or 09, I'd estimate he's put 80-90k on the truck since then. Pretty impressive if the fluid really hasn't been changed since then.

 

It is the 6 lug, which reminds me that I should suggest that he also get the 4x4 serviced if he hasn't done that.

 

Yeah the manual says to do it every 30k miles so it's definitely overdue. As far as the 4x4 system goes, the front differential has the same service interval if I'm not mistaken so it's likely overdue as well (but less likely to be as worn if he doesn't use 4wd often). The manual recommends using 4wd once per month to keep everything lubricated and working properly (10 miles or so), so finding a dirt road or someplace safe to use 4wd every so often is good to do as well.

Same goes for the rear differential and the transfer case, they all take respective gear oil and they're all fairly easy to DIY, so it's probably a good idea to do it all at once if they haven't been done in awhile.

 

In the 2nd gen thread I just remarked that my boss has 438K miles on all his original fluids. Yes including coolant. He says he's added coolant, never changed it. That's an 05 6-spd 4x4. Oh, I'm lying, he had a clutch done at 230 or so K. I'm sure they changed the trans. gear oil then.

Don't sweat it man, manual trans. can take a beating as long as thy have oil in them.

 

Toyota's new ad campaign:

Toyota Tacoma - Truck for the maintenance
adverse

 

I'd never rec'd it of course....in fact I'm kind of a stickler for PM BUT there's prob. just as many trans. get bad synchro's that have had it done every 30K as people who just changed it with the clutch.

 

The power steering and auto trans are the same.
If it's an auto trans. You can disconnect the hose clamps at the radiator. Get longer lengths of tubing. Put a funnel in the trans dipstick tube. Get drain pan. Start it up and drain out some. Shut it off. Fill it up the same that came out. Start it again and repeat.

 

What symptoms is he having with it? Maybe the transmission is fine but the clutch is wearing out.