h150f gearbox input shaft bearing replacement, how hard is it, and could it just wait till the gearbox gets re built?

[thebokworm]

so have had a rattle intermittently when at low throttle high torque, I assumed and confirmed it when I pulled the gearbox to do the clutch upgrade.
the part im looking at is 200 bucks for the bearing alone.
its not a lot of play but just enough to know its not supposed to do it, it does get a little host every now and again when doing longer highway driving

should I pull the box apart and replace the the bearing or just leave it and stick the box back in after the clutch
any advice would be great
Cheers

 

[PIP]

I was a transmission builder for a few years. Owned the shop.

I've never seen a transmission with one bad bearing. Aisin manuals are all very simple transmissions with ball and roller bearings. When they get sloppy you need to replace all the bearings. Not one. A good quality rebuild kit should be a few hundred bucks for bearings and brass.

 

[thebokworm]

I was a transmission builder for a few years. Owned the shop.

I've never seen a transmission with one bad bearing. Aisin manuals are all very simple transmissions with ball and roller bearings. When they get sloppy you need to replace all the bearings. Not one. A good quality rebuild kit should be a few hundred bucks for bearings and brass.

How difficult is a rebuild on one of these, or is it just a pull apart and slide bearings off.
Could the rebuild be done with basic tools on garage floor, or more of a shop setup, the transmission is already off

 

[ikarus]

It's a fair amount of work but the FSM lays it out pretty well. Do you have a factory service manual?

There's a resource section on this site but I can't remember if they have the right manual. You can also go to this group on Facebook: Facebook - https://www.facebook.com/groups/1649178311965757

Look under "files" and you can download one called "1990fj_hdj_hzj-80_series_chassis& body compressed "

That's RM184E which is the FSM for a 1990 80 Series. It has a manual transmission section that walks you through it. Should give you a good idea of what the process looks like.

There's also a thread on here where a guy did a full rebuild on an H151: H151F Rebuild - https://forum.ih8mud.com/threads/h151f-rebuild.1202461/

I didn't do a full rebuild but I tore down an H152 last year to install an H151 input shaft and while there were a few difficult parts for a casual mechanic like me, it only took a couple trips to amazon/local tool shop to get what I needed. Mainly finding the right pullers.

 

[PIP]

How difficult is a rebuild on one of these, or is it just a pull apart and slide bearings off.
Could the rebuild be done with basic tools on garage floor, or more of a shop setup, the transmission is already off

I would say it's important to have a strong aptitude for taking stuck things apart without damaging anything and having a good grasp of stopping and researching or asking questions before you mess something up. Attention to detail is pretty important too.

I feel most stickshifts are pretty straightforward. Understanding some farmer tricks like how to torch a bearing race off a shaft without harming the underlying shaft whatsoever can get you pretty far. A good medium size 2 jaw puller, a heavy-hitting 1/2" drive impact, a couple styles of GOOD snap ring pliers and a dial indicator will rebuild most transmissions out there.

I attempted, unsuccessfully, to rebuild a 700R4 a few times when I was 15 years old. At 17 I built a TH400 that I daily drove and ran high 12's in a 4k lb pickup. That one working good was a confidence booster! I rebuilt a bunch of D24 and NP205 transfer cases and a couple NP435's in my early 20's. A close friend who owned a gear shop taught me how to setup differentials.

At 23 I was fresh out of the military enacting my plan to start a gasoline fuel injector cleaning business at the exact same time China started offering cheap replacement fuel injectors. A friend started a diesel repair shop and wasn't having good luck with area transmission builders. He asked me if I wanted to try rebuilding an NV4500. I wasn't too keen on it, but he insisted I try. That first one worked great. Then many more after that. I averaged 3.5 rebuilds a week for about 3 years. I mostly did Getrag G360's, NV4500, NV5600, ZF5, ZF6, Aisins (W series, R series, AX5, AX15, etc), Mazda M5OD R1's and R2's. Some old Saginaws, Toploaders, T10's and Porsche transaxles mixed in for excitement.

I researched clearance or preload specs for any transmission I hadn't touched before. Made whatever special tools I needed using a lathe and Bridgeport mill. Bought shim kits as needed. And most importantly- I actually did a good, thorough job.