TC45DA 4WD Ring Gear Fell Off Inside Transfer Case

[Brianslink]

I have a year model 2000 New Holland TC45DA with 775 hrs. The tractor is a recent purchase from a private individual where the tractor was rarely used and kept in a barn. I’ve only had the tractor for a month (60 hours). I was brush hogging on a hill and started to slip just a little so I attempted to engage the 4wd and heard a “clunk”. 4wd would not engage. Took back to the shop and after some head scratching I drained front differential to inspect fluid condition and saw it had lots of shavings in it.
Everything on this tractor appears to be factory and untouched...it still has the factory unblemished paint on the axle to differential bolts. I removed the axle and inside the differential housing I saw the ring gear was loose with ALL OF THE FACTORY BOLTS SHEARED OFF AND BOLTS LAYING IN THE BOTTOM OF THE CASE!! There does not appear to be any thread locker or lock washers on those bolts. My guess is they backed out to the point where they were sheared off. This looks like a factory flub up to not have thread locker or lock washers factory installed here. I will further inspect the case and gears to see if there is other damage and post the solution soon.

 

[RickB]

Yup. By no means the first one to do this. Use the two hole locking tabs when you put it back together. I hope you don't have to replace the ring & pinion.

 

[Brianslink]

After more inspection there is no adverse damage to the ring and pinion. I was lucky enough to identify this problem before major damage was done and costly parts needed. I did have to clean up two of the thread holes in the ring with a tap. I purchased all new grade 8 bolts plus lock washers and thread locker then re-assembled the ring to the carrier. All in all about $40 in bolts, washers, thread locker, gasket sealer and fluid. I bet this would’ve been considerably more at the dealer. It took about 4 hours to complete including draining and refilling the final drives since I was in the mood.

This should not have happened as this should have been assembled correctly at the factory. Mistakes happen I guess.

 

[LittleBill21]

not to burst your bubble, but 8.8 is not equivalent to grade 8 sae, its equal to grade 5. 10.9 is equal to grade 8 in metric.

 

[RickB]

not to burst your bubble, but 8.8 is not equivalent to grade 8 sae, its equal to grade 5. 10.9 is equal to grade 8 in metric.

Correct, and the lock washers will do more harm than good over time. Loctite was a good call, lock washers were a poor choice.

 

[crazyal]

I've never seen locktite used on a ring gear. Usually they are a tight fit and torquing the screws down is all that's needed. It does look like the teeth on the ring gear do have some damage but I think you'll be ok. I would drain the oil after a few hours of use and check for metal. If you haven't put it back together yet I would put a magnet inside it to attract anything metal loose inside there.

 

[RickB]

Loctite is part of the factory guidance for this particular failure along with the use of locking tabs. There is no reason not to use it.

 

[inpo44]

A good friend and I both bought new TC45D’s in early 2001. Both of them failed like that before we hit 50hrs. The dealer said it was a factory defect and it was repaired under warranty.