No fill port in the engine bay for the manual transmissions. The drain and fill plugs are 24mm bolts located on the driver's side of the transmission. Remove that wheel and move the fender liner out of the way and you can access them. If you open the fill plug when the fluid is warm it should just slightly seep out. Then you know the level is fine.

It's very easy to change the fluid and only takes 2.2 bottles of the Volvo stuff.

 

Thanks Will. I thought I had seen something about an under-hood fill spot ("port" was probably not the right word), and after I posted my question I searched (I know, I know) and found this. Apparently it's not too well known. -->

I own a 1998 V70 with a 5speed as well. Drain the oil out the drain plug on the left side of the car, you will need to take the left wheel off. It is easy to add the new oil from the beneath the hood by removing the back up light switch from the top of the transmission, it is just behind the breather box. Good Luck

 

Sorry I thought you were asking if there was a place to check the level from the under the hood which there is not. I always fill mine through either the reverse light switch port as described above or you can remove the blue vent cap on the top as well and fill through there which is the other way I've done it but it's a small hole so there is usually some spillage with this method.

 

No no. My bad for not being clear with the question! I assumed if you could fill underhood, it might also be possible to somehow check the fill level there.

 

I've got the air intake out of the way and can see the blue cap and the reverse light bolt. It looks like the reverse light bolt is a 21 mm (deep socket), which I don't have but could get. The blue cap looks like the easier way. However, the blue vent cap is quite a bit higher than the reverse light bolt. I know it's 2.2 Q, but how "full" is full when you're topping it up?

 

Don't top it up! Change the fluid the right way. This is really very easy.

-Loosen the bolts for the left front wheel.
-Jack up the car from the jack point under the driver's side (roughly under the door).
-Remove the wheel.
-Lower the car slightly so that gravity will be working with you when draining out the old fluid (just be careful to not let the brake rotor hit the ground)
-Locate the 24mm drain plug. It should be just below the subframe and easily accessed with an open-ended 24mm wrench.
-With an oil pan below, open the drain plug and let all the fluid drain out.
-With a new crush washer, close the the drain plug and tighten. I think it's supposed to be 28 ft lbs but it should make the washer crush.

-Attach a thin clear tube to the bottle of gear oil and fill through that blue vent cap being careful not to spill.
-Re-install the air intake.
-Re-install the wheel.
-DONE!

 

Awesome step by step, Will. I bookmarked it for later. I ended up drizzling in an ounce or two through the blue cap and called it good, since I wasn't comfortable just doing it blind. Glad I stopped! I'm running Mobil 1 Gear Oil right now, but want to try a higher grade fluid next time, like Royal Purple, and will be glad to have your instructions when I do. Thanks!

 

Glad I could help. I normally love Royal Purple stuff and I use their Gear Max in my rear diff on the wagon. I used it in my M58 for a few thousand miles but decided to change back to the Volvo stuff when I read that the Volvo stuff is a GL-4 fluid with a pretty narrow viscosity range where the Gear Max is a 75w90 GL-5. I know it says that it's supposed to be fine for GL-4 applications as well but I've also heard that GL-5 fluids are hard on the softer metal that is in GL-4 applications and ever since my friend Ben's M56 grenaded this summer running with RP for the past year I felt a little nervous about it.

It's probably just being overly cautious though. Maybe you could try Redline MTL? I think that is a GL-4 fluid.

 

Redline was going to be my other choice. Just checked the Mobil 1 bottle and it's GL-5 also. Assuming it is indeed GL-4, Redline it will be. Thanks for the infos.

 

Redline does make a GL-4 in 75W90. It's called "MT-90". This is from the website:

"Safe for brass synchros, as it lacks the reactive sulfurs found in most GL-5 oils that cause damage"

The Mobil-1 oil does stink like sulfur. Wish I had known this before I put it in.

 

Exactly - Redline also makes their synthetic MLT which is a 70W80 GL-4 just like the Volvo stuff. I'm sure the MTL or MT-90 is just fine. Good to know the Mobil 1 stinks!

 

Which is the weight that is recommended? I checked the owners manual and could not find a recommended gear oil for manual transmissions. When I went to a Volvo dealer yesterday to get a crush washer--after checking my VIN, the computer recommended a Volvo fluid that was a GL5 (for a ridiculous price). I throw up my hands.

 

Parts depts. typically are completely clueless most of the time. When you find someone in Volvo parts who is good at what they do you have to keep going to that person.

The back of the Volvo Manual transmission fluid bottle says: API GL-4, SAE 75W-80. So it's a pretty narrow range synthetic.

The angle gear oil and rear diff oils are GL-5 (the rear diff one has a low friction additive)

 

Extremely valuable info. I'll look for the Redline MLT then.

 

I did the job today. You don't have to remove the the wheel if you fill from the top, which I did. I cut a small piece of cardboard about 6" x 14" and draped it over the frame to prevent the draining oil from dispersing along the lip of the frame and creating a "Niagra Falls" and a big mess like it did last time. Used a new aluminum crush washer and tightened it back up. Then to refill.

First tried the blue cap hole, but it overflowed too easily, so I bought a 22mm deep socket and used the reverse light probe port instead. It worked great. Got some 3/4" (I think it was) plastic tubing and poured the Redline MTL into the old Mobil-1 bottle I had standing around like feeding plasma to a patient. The Redline bottles do not come with nozzles and the necks are too small to swap the nozzle from other bottles. The tube fed the oil in beautifully through the reverse light port. I added 2 32-ounce bottles plus around 6 ounces (2.2 quarts).

Shifting feels about the same as before, but it feels good to have the GL-5 sulfuric blend out of there. EDIT: After a couple of days' driving, it is noticeably better.