Removing NP435
Posting Guru
Joined: May 2002
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From: Bryan/College Station
Tater, I can't believe you have to ask that question. 
For safety reasons you should disconnect the negative cable before pulling the tranny. On the other hand, if you use your tater force and don't turn the key to the start position, you can safely just unhook the cable from the starter and leave it hanging.
Noise in 1st, 2nd and 3rd but not 4th (direct drive) is a result of a problem with the pocket bearing which sits in the back end of the input shaft and supports the front of the mainshaft. If you are going to take the time to repair the tranny, do it right and replace all the bearings including the countershaft bearings.
Also, when removing and installing the trans do not let it hang from the input shaft. Damage will occur to the clutch hub or input shaft.
Chris
For safety reasons you should disconnect the negative cable before pulling the tranny. On the other hand, if you use your tater force and don't turn the key to the start position, you can safely just unhook the cable from the starter and leave it hanging.
Originally Posted by Bdox
You have a lot of good info above for this job.
I would add that both the t-case and the transmission are difficult to balance on a floor jack so it is a good idea to recruit a helper for the in and out part. Drain the trans first because it will save some mess and you are going to get into it anyway.
I had the same problem with my np435 and all it needed was new bearings. It is just fore and aft wear that allows it to jump out of third so you most likely don't have to mess with the countershaft bearings unless you are hearing constant noise in first, second and third.
I would add that both the t-case and the transmission are difficult to balance on a floor jack so it is a good idea to recruit a helper for the in and out part. Drain the trans first because it will save some mess and you are going to get into it anyway.
I had the same problem with my np435 and all it needed was new bearings. It is just fore and aft wear that allows it to jump out of third so you most likely don't have to mess with the countershaft bearings unless you are hearing constant noise in first, second and third.
Also, when removing and installing the trans do not let it hang from the input shaft. Damage will occur to the clutch hub or input shaft.
Chris
Fleet Owner
Joined: Sep 2005
Posts: 28,609
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From: Lake Tahoe, Nevada
Chris,
you are right about the input shaft bearing. But it is also true that countershaft bearings are loaded in 1st, 2nd and 3rd but not in direct (4th) so they will make much more noise in the lower gears.
The input shaft bearing and any bearings on the mainshaft, plus any thrust surfaces are in question when the trans is jumping out of gear.
you are right about the input shaft bearing. But it is also true that countershaft bearings are loaded in 1st, 2nd and 3rd but not in direct (4th) so they will make much more noise in the lower gears.
The input shaft bearing and any bearings on the mainshaft, plus any thrust surfaces are in question when the trans is jumping out of gear.
Posting Guru
Joined: May 2002
Posts: 1,306
Likes: 0
From: Bryan/College Station
Originally Posted by Bdox
Chris,
you are right about the input shaft bearing. But it is also true that countershaft bearings are loaded in 1st, 2nd and 3rd but not in direct (4th) so they will make much more noise in the lower gears.
The input shaft bearing and any bearings on the mainshaft, plus any thrust surfaces are in question when the trans is jumping out of gear.
you are right about the input shaft bearing. But it is also true that countershaft bearings are loaded in 1st, 2nd and 3rd but not in direct (4th) so they will make much more noise in the lower gears.
The input shaft bearing and any bearings on the mainshaft, plus any thrust surfaces are in question when the trans is jumping out of gear.
Your second statement is true more or less but that was not what I was addressing.
Chris
Fleet Owner
Joined: Sep 2005
Posts: 28,609
Likes: 18
From: Lake Tahoe, Nevada
Originally Posted by brokebronco
As usual you know it all. However, if the countershaft had a bearing problem it would make noise in all gears. If the noise is only in the first three gears but not direct drive (4th) it is the pocket bearing located in the rear of the input shaft.
Your second statement is true more or less but that was not what I was addressing.
Chris
Your second statement is true more or less but that was not what I was addressing.
Chris
And you are right about the 'pocket' bearing, in fourth the mainshaft turns at the same speed as the input shaft so that the 'pocket' bearing doesn't turn.
Also a fact: the countershaft bearings are loaded in 1st, 2nd and 3rd but not in direct (4th) so they will make much more noise in the lower gears.
Fleet Owner
Joined: Sep 2005
Posts: 28,609
Likes: 18
From: Lake Tahoe, Nevada
Originally Posted by sierraben
I heard that worn out syncros can cause the trans to jump out of gear.
Is there any truth to this?
Is there any truth to this?
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