Manual Transmission Fluid

[datzenmike]

Paul if the Redline is synthetic or semi/synthetic it's very likely it will seep as it is extra slippery and will pass old or worn seals too. The speedo cable, when unscrewed, has a small quarter sized rubber disc on the end with the inner cable poking through. This is a seal of sorts to prevent oil climbing the spinning cable to the gauge in the dash. You may have noticed wetness there. If missing a replacement might solve this.

[Paul G.]

Redline oils are all fully synthetic. The stuff looks like AFT, pours like water, and shifts like butter. I'll have to look for that washer next time I want to spill some GL-4. I drove without the gauge cluster in place for awhile and oil doesn't seem to be making it to the top of the cable. I'm pleasantly surprised none is making it past the driveshaft seal.

[datzenmike]

The speedo drive is high enough on the tail stock that fluid won't leak out. You are only unscrewing the cable anyway so nothing will pour out. If you look in the cable end, there is where the rubber disc should be. I need to pull my 710 speedo cable off to see why it works intermittently since Canby. Worst comes to worst I can put a 620 cable on. I'll try to take some pictures of it.

[CorAce]

Wow, I glad I found this thread. I just swapped oils in my dogleg about a week ago with a Lucas product. It’s meant for autos but it has a panel on the back that says its good for light duty manuals as well. I’ve used it in newer manual with good results, but ever since I put it in my dime its been whining like crazy. I didn’t put it together until I read this tread. This stuff is super thick, should I try to flush it out or can I just drain and add GL-4?

[datzenmike]

So it's ATF?? Usually it thinner than motor oil. My son's old Grand Am used engine oil in the FWD manual tranny. So anything is possible with these newer cars.

 

Just drain over night and refill. If worried get a couple of quarts of Dexron ATF and fill and drive around the block, drain and refill with GL-4. I flushed a tranny with ATF by rolling it around on the lawn and draining it before installing. No biggie.

[CorAce]

ya I think so... I tosed the bottle already. but if memory serves its for High milage autos. its super thick and red. it took over an hour to drain a quart through a langth of fuel line into the trans

[datzenmike]

Yeah it won't be good enough protection over the long run. Refill and the whine will likely go away.

[datzenmike]

Redline oils are all fully synthetic. The stuff looks like AFT, pours like water, and shifts like butter. I'll have to look for that washer next time I want to spill some GL-4. I drove without the gauge cluster in place for awhile and oil doesn't seem to be making it to the top of the cable. I'm pleasantly surprised none is making it past the driveshaft seal.

 

Here's the speedo cable with the drive pinion connected to it. The tranny output shaft has a worm gear on it that turns the blue cog and spins the inner cable inside the outer sheath of the speedo cable assembly. The O ring keeps the tranny oil inside the tranny.

 

 

The end of the inner cable has a ferrule with a raised part crimped on that fits into the pinion and locks it so it will turn.

 

 

Just behind the ferrule is a rubber seal shaped like a top hat that helps contain and transmission oil to prevent it climbing up the spinning cable to the speedometer head in the dash.

 

.

[Braden]

hmm thats wierd that the redline didnt do so well, hell i have already bought it i might as well try it out, ill try it and report back, although i did use the stalube and have noticed an improvement, hopefully the redline will work good if not i will drain it and go to the sta lube again, hell i just cant wait for the extra gear!! 4 speed is getting annoying.

[LenRobertson]

So, getting the oil into the gearbox - any cheap n easy, low-tech method? I'm thinking of a pipe thread 90 degree fitting in the fill hole and a plastic tube up beside the manifold with a funnel. Am I getting overly elaborate here?

 

Len

[datsunaholic]

I bought a gear lube pump. Fits the standard bottle. But the cheapest method is just stick a hose in the opening and attach a funnel at the other end. Need a decently long hose though.

[KELMO]

Sounds like what I did only no 90 degree connector. Bagged the funnel and plastic tube, labeled it as to what I used it for, now I got a special tool :D

[LenRobertson]

I took a look under the 510 a few minutes ago. There may not be room enough to screw in a 90 degree fitting anyway. Plastic tubing in the hole should work just fine.

 

Last week I got a gallon of "Sta-Lube Multi-Purpose Hypoid SAE 85W90 Gear Oil API/GL-4, Part No. SL24239" made by CRC. I thought I'd give the full name and number from the front of the jug in case anyone needs to order from a parts house that isn't sure what you want. I got this at NAPA, one of the outlying stores near Spokane, not the main NAPA up there. I don't know if that is a indication most NAPAs stock it. Part of the blah, blah on the back of the container says "Not corrosive to copper, bronze or other non-ferrous alloy bearings and bushings". I got this dogleg at Pull n Save and have never run it in a vehicle. I've been concerned if it is a good working tranny, but now I have faith this Wonder Oil will make it like new!

 

Len

[KELMO]

So, Len, just curious...what did NAPA charge for a gallon up in your neck of the woods?

 

Kelly

[LenRobertson]

Kelly - I think the gallon was about $26, plus 8.7% WA sales tax. I got the know-someone-at-NAPA discount it seems. Getting a discount does keep me going back there, plus the store is way easier for me to get to than the other chain auto parts places. I do struggle with the NAPA website. I always get a run around where it want to know where I live so it can tell me the closest stores, when all I want to do is check if NAPA has the part I need. I suppose there is a way around the store locate game, but they need to dumb it down for me.

 

The price of the Sta-Lube, whether discounted or the $30+ full price, seems a bit much at first. But compared to the cost of a tank of gas, and considering a gallon will do two trans fills, it really isn't too bad. It's a one time expense, unlike the gas tank fill. Also, I'm sure it will make my 30 yr old dogleg work just like new. Just like installing a magical Elephant Oil Cap on the used L20b I'm putting in the 510 will make it like a new engine. If I'm wrong about that and the engine is a real smoker, well it is mosquito season, so the smoke will be useful.

 

Len

[datzenmike]

Change the fluid every 5 year/ 30K miles and you should be trouble free. That's $6 a year.

[LenRobertson]

I finally filled my dogleg this afternoon. I ended up getting 3 feet of the clear plastic tubing with the white braid inside. My parts place was out of stock on the clear-without-braid, but the guy said it tends to kink anyway. I think the inner diameter is 3/8 inch. I hooked the tubing to one of those long, skinny plastic funnels using a short length of heater hose and hose clamps. I swiped a one pint Pyrex measuring cup out of the kitchen and measured out the 3 and 5/8 pints needed, so I wouldn't overfill it and have oil overflowing on my slab. It all worked very well, except when I took the cap off the gallon oil jug I somehow sloshed oil onto the engine and it ran down the exhaust manifold. So I can look forward to the yummy burned oil smell when I do the initial startup. And that day is getting closer and closer, maybe even tomorrow, if I blow off mowing the lawn. Running 510 of my dreams!

 

Len

[AZ_L320]

Here's the speedo cable with the drive pinion connected to it. The tranny output shaft has a worm gear on it that turns the blue cog and spins the inner cable inside the outer sheath of the speedo cable assembly. The O ring keeps the tranny oil inside the tranny.

 

 

The end of the inner cable has a ferrule with a raised part crimped on that fits into the pinion and locks it so it will turn.

 

Just behind the ferrule is a rubber seal shaped like a top hat that helps contain and transmission oil to prevent it climbing up the spinning cable to the speedometer head in the dash.

 

 

Hey Mike, I was wondering if you can help me? I was searching on Ratsun about Speedometer cable seals and found this thread. Unfortunately I can't view your pictures from work (they block Photobucket), so I will have to look at them when I get home.

 

Anyway, I have a 620 with 4spd that leaks oil from where the speedo cable goes into the tranny. Will just replacing the "top hat" shaped rubber seal do the trick or do I need to replace the o ring your talking about??

 

Do you know where I can find the "top Hat" seal for a 620?

 

Here is a picture of mine (I hope this works, I can't see it right now (dang work).

 

Thanks for any help,

Dale - Arizona

L320 & 620

 

 

[datzenmike]

32710 14600 is the Nissan part number for the 'O' ring for the pinion. About a buck.

 

Can't find anything for the 'top hat seal'. A new one would be on a replacement speedo... about $20. If you thoroughly clean it and degrease you could seal with RTV, assemble with the old 'hat' and let set over night. I hate that stuff but should work.

[AZ_L320]

Thanks Mike, Your a big help. While we are on the subject I have another question. I removed the roll pin and the center shaft from the drive gear. There is also an internal seal there. Any ideas where one can get this seal? Is there a Nissan part number for it? Here are a couple pictures of what I'm talking about.

 

I'm thinking if there is leak from the speedo drive gear, it could be from either the O ring or the interanl seal. If both of these don't leak, then oil shouldn't even get to the top hat seal. But if either one is bad then it could.

 

Thanks again,

Dale - L320

 

 

 

[AZ_L320]

Hey Mike,

Update, I think I found the part number for the seal. 32709-14600. I hope thats it. I ordered both for my 620. That should take care of my leak, I hope.

 

Thanks

Dale -- L320

[69dime]

GL-4 80-W-90. This is what Nissan recommends. Don't let someone from an auto parts, dealer or where ever you buy oil try to tell you that GL-5 is the same, or better, or and up grade. These trannys are older and have brass synchros in them that will be attacked by the higher anti scuffing sulphur compounds present in GL-5 gear. GL-5 is just fine in differentials. Some newer cars use steel synchros so GL-5 can be used and this is where the confusion begins.

 

You can also switch to a good synthetic if you are rebuilding it. Old seals/gaskets tend to leak synthetic oil because it is so slippery.

 

My shop manual says GL-5 for sedan rears but GL-4 for wagon rears. I can shoot a picture of it if you guys would like to see it.

[datzenmike]

The 510 goon uses the same H-190 diff as the truck. GL 5 is indicated for them. Transmissions transmit power in the same axis of rotation. Differentials transmit through 90 degrees and there is more 'rubbing' of the contact area on the teeth. Sulfur additives prevent scuffing but harm brass synchros in trannys.

 

I'd like to see the manual quote but only if it's a factory shop manual (FSM) from Nissan. All others are suspect.

[datzenmike]

Hey Mike,

Update, I think I found the part number for the seal. 32709-14600. I hope thats it. I ordered both for my 620. That should take care of my leak, I hope.

 

Thanks

Dale -- L320

 

 

Sorry Dale I just stumbled over your posts.

 

32709-14600 is correct and there is an O ring too... 32710-14600

[69dime]

The 510 goon uses the same H-190 diff as the truck. GL 5 is indicated for them. Transmissions transmit power in the same axis of rotation. Differentials transmit through 90 degrees and there is more 'rubbing' of the contact area on the teeth. Sulfur additives prevent scuffing but harm brass synchros in trannys.

 

I'd like to see the manual quote but only if it's a factory shop manual (FSM) from Nissan. All others are suspect.

 

It's a early factory shop manual, which I think looks identical to the Clymer inside. I'll send some pictures. Also some pictures of the GL-4 I got from NAPA with the part number and the part number of the pump.