Rattling noise in neutral when cold (SM465?)

[Chris Demartini]

<font color=blue>When I start my truck cold, it makes a rattling noise in neutral. At first I thought it was my bumper but it was tight. It goes away as soon as I put it into gear. I crawled under my truck today when I started it and it sounds like its coming from the trans. Could it be a bearing? This only happens when its cold. I have an 83 1 ton SM465/NP205 in my crap storage facility (garage) but the 205 is slip yoke. That trans should bolt up to my stock 205, right?

<font color=blue>pavement queen with shinny paint job and car tires</font color=blue>

 

[Shawn]

You should use the 83 since the front output shaft should have more splines than your older 205. Take off the front yoke of each t-case and you'll see. It should bolt up with no problems and then you can swap the rear output fixed yoke. Another fix I've heard of for noisey trannies is synthetic gear oil but I'm not sure since I've never had manual problems.

Shawn
87 K5
few mods

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[Sparky]

that noise is probably just your throw out bearing, it is a pain to replace because you have to pull the tranny, but not hard after that. Look it up in a Haynes or Chiltons.

When all else fails... Check the blinker fluid.
78 K-5

 

[Sparky]

that noise is probably just your throw out bearing, it is a pain to replace because you have to pull the tranny, but not hard after that. Look it up in a Haynes or Chiltons.

When all else fails... Check the blinker fluid.
78 K-5

 

[Chris Demartini]

<font color=blue>The noise happens with the clutch pedal not depressed, so I dont think its the throwout bearing. I used a new throwout bearing when I put the Centerforce clutch on back in Oct 99 when I put in the new motor. Will I be able to bolt up my fixed yoke in place of the slip yoke without modifications?</font color=blue>

<font color=blue>pavement queen with shinny paint job and car tires</font color=blue>

 

[Wheels]

Push in on the clutch and see if the noise goes away (without putting it in gear). If it quits, probably the throw out bearing. But you stated that it quits when you put it in gear. Another thing you may want to consider is the gear lube. Petroleum based gear lube gets really thick when it gets cold. When it get's really cold it will act as if your brakes a on. I've run synthetic gear lube in all my vehicles since I moved to the midwest. I had a 68 Bronco that would do this on cold mornings (17 degrees) and I swapped out to synthetic and it never happened again. AMSOil and Valvoline currently offer synthetic gear lube. I had both in my 79, AMSOil in the front and Valvoline in the rear. When I changed gears recently, I pulled both covers and it seemed to me that the Valvoline was a little more sensitive to temperature than the AMSOil was. The temp outside that morning was 21 degrees before I pulled it in the shop. Anyways, they both have AMSOil in them now. Just my nickels worth. As far as the 465/205, I just posted some information on the slip yoke that may be of interest to you, but it will bolt up. Good luck.

 

[Chris Demartini]

<font color=blue>I just went out and started it, I didnt push the clutch at all and it still made the noise so its not the bearinf. I'm going to try the oil trick next. I'll have it in a shop this weekend to do some ignition work and change the oil so I'll do it then. I have also noticed that its hard to get into 2nd when its cold. Other SM465s I have driven do this too.</font color=blue>

<font color=blue>pavement queen with shinny paint job and car tires</font color=blue>

 

[FWP]

Mine does the same thing. I think it's one of the gears idling inside the tranny, no big deal.