T19 noise

Hondo

Hondo

Member
Have a Wide T19 with a Dana 300 behind it in a 75 Scout II. Am getting a loud ringing/growling noise coming from the transmission cover on the freeway over 50 mph. This only happens when I lift off, or step on the gas, and stops fairly quickly. Cruising steady state there is no noise. Thought it was a problem with transfer case shift arms or bull gear, so pulled the cover on the D300 to look. Everything in there looked good, but I can move the bull gear and transmissions main shaft in and out about .012 to .015 (used feeler gauges). I can see the nut holding the bull gear on moving in and out with the gear, so its not a matter of the bull gear being loose on the transmission output shaft. Measured between the end of the D300 output shaft and the end of the bull gear. Can't find a spec for this end play anywhere, but the Close T19 on the garage floor doesn't appear to have any. Does anybody know how much if any end play there should be before I pull the Wide T19 out ? I kind of equate swapping these trannys with having a root canal.
 

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I run Redline synthetic MT 90, in both The T19 and the D300. I bought the Wide T19 used, and it had some water in it, for who knows how long. Cleaned it up and flushed it out several times before installing it. Basically wanted to see if there were any problems with shifting, weird noises, etc. Its been running for at least 10K miles since then. Think it's probably the rear mainshaft bearing going south.
 
From my experience, what you are describing sounds like gear clash in the transmission or transfer case from most likely a not perfect rear driveshaft angle. As the driveshaft goes round and round, the driveshaft is speeding up and slowing down, but has a load against it. When you take the load off of it(decel), the driveshaft is still speeding up and slowing down so it makes the gears clash. Check your ujoints to make sure you don't have a bad one. If all looks good I wouldn't worry too much about what you are hearing unless more metal starts showing up in the oil.
 
Thanks Jeff, Ill definitely check that out. Recently went from a 2 inch to a 4 inch spring lift, then installed 2 inch longer shackles front and back. Installed 4 degree shims to tilt the rear diff up in the back, might be too much with the additional tilt from the longer shackles. Probably should get the rear driveshaft lengthened a little as well. Think a CV joint at the Transfer case might help?
 
A CV driveshaft will help, but regardless of which way you go it sounds like you'll need to tweak the rear pinion angle.
 
Thanks Jeff. I did a little driveshaft home work, and looks like I shot myself in the foot installing the shims to point the rear diff up without going to a CV joint at the transfer case. For now I'll pull the 4 degree shims out and see if that helps, I installed the shims a few weeks before the longer shackles, and didn't notice the problem until I installed the longer shackles. Guess things just kind of stacked up. Problem is made worse by the longer 6 cylinder, and the longer heavy duty output shaft on the D300 making for pretty short, steep, jeepish rear driveshaft.
 
Pulled the 4 degree axle shims out of the back, and it didn't make a whole lot of difference. Crawled underneath and tried to find something loose. Frigging big nut holding the yoke on the transfer cases AA heavy duty output shaft was backing off, letting the rear output shaft wiggle a bit. Pulled the nut off, re-applied some silicone to the back of the nut, added some locktight to the threads, and re-torqued the aircraft nut to 150 ftlb. The axle shims are staying out for now. From what I read, if the driveshaft only has two u-joints, the yokes of the transfer case, and the rear differential are supposed to remain parallel within a couple of degrees. Being offset is OK as long as it is not too much. Not sure if something "wore in" or the nut just backed off, but will definitely be checking it anytime I'm under the Scout from now on.
 
Glad you found the issue. If that nut backs off again I would suggest replcing it with a new one. If you tell me what size socket it takes, I can tell you if that nut is the same as a Dana 44 axle or Dana 60 axle as we stock both.
 
Was still getting a little noise from the transfer case after removing the 4 degree shims that were tilting the rear diff. up, so pulled the drive shaft and slapped a spare U-joint into the yokes to accurately measure some angles. Transfer case yoke was pointed down 4 degrees, and rear diff. was pointed up 8 degrees. Pulled the rear springs back out and put the 4 degree shims in from the back, so rear diff. yoke was only 4 degrees up. This put it parallel to the transfer case yoke. I am getting no noise at all now. Figured I had probably considerably shortened the drive shafts u-joints life, so replaced both of them. Headed up to Pyramid Lake in Nevada for the 4th, so the new setup will get a good test run. I highly recommend this most excellent driveshaft 101 article. http://www.pirate4x4.com/tech/billavista/PR-shaft/index2.html
 
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