2004 WRX Manual Transmission Fluid Change - Observations

I've been seeing comments lately on NASIOC about staying away from synthetics in the MT. Did you have problems with 1st & 2d before or after the change to Redline?

Steve

Yes. I asked someone in a dealer service dept when I had something installed. He said it's fairly common for Subaru manual transmissions to "crunch" going into 1st/2nd gear.

It's not buttery smooth like a Honda stick, but it is shifting much better now.

I think that synthetics that are properly formulated for use in a manual transmission should be fine. The biggest problem I've heard of is people using synthetic motor oil in trannies designed for motor oil as the fluid.

Where did you order the socket from? Thanks! Does it normally take a month to ship?

I posted it in an earlier thread. I got it from Toolsource.com for $21.95 + shipping for a Stahlwille 54TX-T70 1/2" drive socket. I also got a torque wrench, which was in stock and shipped last month. The socket was out of stock, but they kept me updated on when it was expected to come in. Their customer service was very good - They gave me the option of cancelling the order.

** ** ** **

Here's a picture of the part next to a quarter:

Most of my tools are Craftsman from Sears, which are high enough quality for this DIY'er. However - I hear that the quality of Stahlwille tools is perhaps the highest in the industry. For $22, it better be really, really good.

don't extract the fluid... better a tad high than a tad low. remember, there is no oil pump in the mt5, so there's no terrible danger in frothing. in fact, i don't think it's even a problem in the first place, so rest easy.

it takes a few days to really get the gear lube in all the tight spaces. expect the shifting performance to continue to change for the next hundred miles or so as a result.

jm2c ken

Just a follow-up:

The change amount in the owner's manual is 3.7 US quarts. I actually drained a little over 3 quarts of the factory gear oil (when I stored the used oil in bottles). Previously, I'd check the dipstick with a warm engine, but long after the fluid had time to drain back - the level was right at the full mark. The manual seems to state that the fluid should be checked right after the engine is shut off. When I did that, the fluid level was between low and full. Anyone know if there's a preferred time to check the transmission fluid level?

In article

, snipped-for-privacy@ride.ri.net says...> it takes a few days to really get the gear lube in all the tight

Ken,

I saw an old (nasioc?) forum thread where you mentioned addition of a few ounces of "synchromesh fluid"...what the heck is that, and where did ya find it? Still feel that it was beneficial?

Steve

Had the same problem with my 02 WRX. Don't let them tell you it's normal for the "crunch" to happen. I keep on my dealers a** and the finally found that the first gear syncro was worn. After they replaced it, I have NEVER had another "crunch" sound.

I believe "Synchromesh Fluid" is a special manual transmission fluid spec'ed by GM and/or Chrysler. My guess is that it contains special friction-enhancing additives to help with synchronizer engagment. I believe Redline uses similar additives in MTL/MT-90 and 75W90NS, as does BG with their "Synchro Shift" manual tranny lube.

Hmmm...ok, reading up on it. I'd love to hear if anyone tried it and liked it (long term). Never seen this stuff on the shelf...

Steve

absolutely, steve.

when i top off the tranny, i use the syncromesh fluid. i have very good syncro performance, despite using the very slippery mobil 1 synthetic 75w90 mt gear lube. i absolutely NEVER crunch in 2-5, and only when _really_ rushing 1st do i get a little chatter. cold weather performance was much better than oem dino fluid too.

in the rear end the mobil 1 goes in uncut. it's nice to be able to get my lube needs at the local autozone.. no having to hunt high and low for some esoteric lube that costs an arm and a leg either.

fwiw, a lot of guys in the DSM world use the synchromesh fluid uncut.

hth ken

I thought one of the potential problems with API GL-5 gear oil is that it needs friction (reducing) modifiers to make it compatible with limited slip diffs. That's Redline's alleged reason for the 75W90NS (no-slip).

The Redline 75W90NS I used is **NOT** API GL-5 rated; the label says "Recommended for API GL-5". This seems to be similar to their recommendation of MTL/MT-90 in place of engine oil or ATF in manual trannies. Redline claims that the friction modifiers in regular API GL-5 hurts synchro engagement. They have an LSD additive for the 75W90NS, but I suppose they'd prefer their

75W90 be used in an LSD.

I have a bottle of Mobil 1 75W90 for the rear diff, and yes - I did buy it at AutoZone. I chose the Mobil 1 for the bottle shape, which looks like I can fill the rear diff by squeezing right out of the bottle. I'd need a pump (or maybe turkey baster) for the regular Redline bottle.

Any recommendations for the rear diff? Any gaskets/washers/ sealants needed? I noticed some gray stuff that looks like a hardened sealant around the drain and fill plugs. Any good way to clean this stuff off?

I found that the best prices and selection for Redline in my area (SF Bay Area) is at a place called Vic Hubbards Auto Supply. The Redline gear lube was $7.69/qt, which is a shade more than the $6.99 for Mobil 1 gear lube.

Really?

DSM...you got me on that one.

Alright...is this the "Quaker State Synchromesh" Fluid that y_p_w mentioned? Does it come in "weights"?

Steve

dsm diamond star motors, the joint mitsubishi/chrystler venture that produced the eclipse/talon/laser lineup... another turbocharged 2 liter awd platform that tends to munch up drivetrain parts.

personally i have never used quaker state's version of the synchromesh, only pennzoil's. it only comes in one weight.

ken

cobb has some good info here:

yes i didn't need any hoses or pumps to change the rear diff fluid... i ended up with a mobil 1 bottle that i squeezed like a tube of toothpaste, rolling from the bottom and flattening as i went up. worked fine.

get a good long breaker bar or rachet wrench for the plugs.. they're on "factory tight." i'm skinny so i just backed up onto a pair of

2x8's which provided more than enough clearance to wiggle under the back of the car. you do not need to take off anything that's on there well, but it's a good idea to take a brush to the area to remove loose dirt to insure none gets in there as you've got the plugs out.

HINT: remove the TOP plug first... they're tough to crack open sometimes, and if you take the bottom one out the fluid will be drained and then you HAVE TO get that top one out, no matter what, before you can drive the car. if you fail at the top plug first at least you can continue using the car!

hth ken

Pennzoil seems to be the one I've seen in stores - Pennzoil and QS are now in some marketing agreement with Shell. There may be other aftermarket makers of Synchromesh fluid.

Here's two ACDelco parts:

Part 10-4006

88900333 Synchromesh Transmission Fluid

• Partially synthetic * Excellent lubrication properties * High-and-low temperature-resistant * For manual transmissions

Part 10-4014

88900399 Synchromesh Manual Transmission Fluid (Friction Modified)

• Contains a semi-synthetic lubricant compatible for use in NV 1500 transmissions * Reduces transmission component wear

It looks like they have the two synchromesh fluids, a 5W30 manual transmission fluid, a limited slip diff additive, and two rear axle lubes.

Ken & Y_P_W,

Thanks, I'm gonna take a look for some of this at Autozone..

Steve

Price per quart for synchromesh goes way down if you buy a bucket!

Here's where I got my stuff.

CW