D20 "T" shift clicking noise

[Tiko433]

So I put my D20 in 4 Hi today it has a clicking noise when you drive it . It matches the speed of the truck. I took it to about 45 and the sound just got faster not any louder. It doesn't do it in "LO " or in "2 WH" I had the inspection plate off recently and didn't notice any bad gears . What is the best way to find the problem?

 

[SHX669]

It doesn't do it in 4 lo but does it in 4 hi ? - hmm - how fast were you driving in 4 lo - maybe you weren't driving fast enough to hear it or stress it enough to make noise.

 

[Tiko433]

When it's in 4 Hi you can hear it as soon as the truck rolls. The sound will match as the speed goes up. Yes in 4 Lo or 2 Hi it doesn't make the noise at all. I drove to about 20 in 4 Lo I didn't hear anything odd

 

[DirtDonk]

Are you driving on hard packed surfaces with good traction? If so, don't do that for very long or things will bind up. Yes, you can do it, but it's not recommended in general terms.

But a clicking could be the shift lever touching the floor when it's all the way back like that.
Or it could be not quite fully in gear.
Could be a bearing, but doubt it.
Have you verified the fluid level? Changed it lately? What weight? Recommended weight is 50wt motor oil, but many of us use a very thin and "flowy" synthetic gear oil with good results.
How many miles on the box?

Anyway, check the linkage at least and make sure it's not hitting the floor.

Paul

 

[Tiko433]

I know not good for it but yes this was on dry pavement. We have some snow coming and wanted to check it . I did the transmission 2 months ago so the T case has fresh fluid. I know I didn't put 50w in it . I think I did 70-90 It didn't have a stock shift selector, I'm using a rubber boot I removed it to make sure the shifter wasn't touching anything. I don't know if it's ever been rebuilt.
When it's in 4Hi are both rods pulled out equal lengths ? Both mine look like they are out all the way .
I will see how it does in the snow

 

[Rustytruck]

When I have dealt with tic tic in 4-wd it was usually a front hub not sliding fully into the lock position. Jack up each front wheel and put it in lock and turn the tire and make sure its locking in.

 

[DirtDonk]

Well you covered most of the bases. Rusty hit it on the head as usual. Unless you're 100% certain that the noise is coming from the box itself (and even if you are), the hub(s) are usually a good suspect to check out.
As is a front driveshaft of course. Even though the clicking is not present in 4-low, the dynamics can be just enough different that a noise might not be the same in low as in high. So while perhaps a longer shot, still worth investigating at this point.

And yes, I think you're correct in that the two rods should be equally out when in 4-high. Same as both all the way in, while in 4-low I believe.
Others will know that better, but pretty sure that's correct.

Paul

 

[Tiko433]

Ok guys thanks for all the good info . Well we got our snow but not the 12in they were predicting . I took it for a spin and it didn't make the noise. So maybe I can chaulk this one up to the driving it Locked in on hard dry pavement.