Transmission lesson

When I drive my Jeep I hear the tranny whining so to speak. Since I've never dealt with an old manual trans, can someone school me on the ins and outs of the T90/T86? I don't know which I have. The transfer case is a Dana 18. I basically just need to know how to do maintenance and what fluids I should use. Everyone has been great and so far the jeep is ten Xs what it was when I got it because of this forum. Thanks

 

If my jeep didn't whine, I'd assume the drive-train had fallen out.

Keep 'em topped with EP 85/90 or similar, to the level of the fill plug on the side. Drain and refill every year or two, or three. Same for the differentials, transfer case, and knuckles.

Use GL-4 spec, not GL-5. Safer for the bronze parts. Can be found on-line or at tractor stores.
http://www.amazon.com/Sta-Lube-SL24...&qid=1445168410&sr=8-1&keywords=gear+oil+gl-4

 

whine could be transmission , but also could be intermediate shaft in transfercase . this is a common wear part . and yes the right oil helps

 

Typically a T-90 will whine in first and reverse, since those are straight-cut gears. One improvement of the T-86 is helical gears on first, which will make it a little quieter. But if you have T-90 gears in a T-86 case, it will sound like a T-90.

You would expect the transmission to be quietest in top gear, since there are no gear faces under load in the transmission when the connection is straight through. However, if you have a worn intermediate gear shaft and bearings, the noise will get louder and increase in pitch as you go faster. The Dana 18 sends power to the rear wheels through the intermediate gear all the time. This makes the D18 quite a lot louder than other geared transfer cases that only use the intermediate gear when in 4WD (like the Dana 20 and Dana 300). This also means that the intermediate gear shaft wears out relatively quickly, and it's a common problem for these cases.

Make sure you've got the right oil in both cases, and give a listen to try and match how the sound rises and falls with which gear you are in and your speed.

I'd suggest you put your year/model/equipment in your sig. Then we can say more.

 

So the trans,transfer and diffs all get the same gear oil???

 

Unfortunately I still don't know what all this beast is! Kind off a bastard child of parts. It's registered as a 66 CJ5. She has the 225 dauntless but I think it's a 71? Has axles out of a later CJ with disk front brakes,power stearing,sway bar and a stearing column out of a YJ I think!! I've only had it a month and I'm learning!!!

 

They all use 90wt, or in modern parlance 85W90 gear oil. Read about GL-4 and GL-5 above, though the oil I use (from Walmart) says GL-4 and GL-5 compatible.

We have a VIN document as a sticky thread that should tell you something about when you chassis was made. The serial number in your VIN should match the number stamped into the frame. The type of transmission is cast into the side of the case - get under there and look.

 

I will. Snowed here in NY last night. Maybe next week when the forecast looks a bit warmer!! LOL

 

Well the front fender is a 71 because of the marker light, but the windshield is earlier because of the top mounted wipers. Does it have the fuel tank under the drivers seat?

That changed in mid 70 to put in the back between the frame rails.

Like Tim said you can research the vin on here or decode it with the factory service manual (FSM) .

 

Fuel tanks in the back. It's a fiberglass tub also. I just put gear oil in. Transmission took almost two quarts and the transfer took a little over one. She sat for a long time prior to me getting her. Glad I checked it before I destroyed it!!!

 

Does the whining noise come from an area down by your ankles, or is it more like even with your knees? The first would be your tranny, the second would be your TC.

 

Hard to tell. My exhaust is loud. Headers and small mufflers. I only hear the sound when I let off the gas and slow down in gear! I can tell a difference in shifting though now that she's topped off! Nice and smooth with zero effort!

 

If a jeep sits outdoors without a roof, the transmission can get water in it, via the shift lever. Might want to check by draining a sample.

 

My trans. made lots of strange noise. I drained it an added this stuff, an refilled it. seemed to quiet it by 50%!!!>>--->>>http://www.mrmoly.com/html/manual_transmission_supplement.html