Thx guys!

cvhyatt: it's not complicated, but you do need the correct tools. I had to order a shim package from ashcroft. I should have ordered a total bearing kit from them, too. Would have been wayyyy easier, but I wanted the green gaskets, and timken bearings...soooo still waiting on parts. Although you could hammer in the races with a drift, I prefer to press them in. So you do need a shop press, and a 'universal press & pull sleeve kit bush bearing removal insertion tool set'(about 100$) that includes 82mm OD tool , and the 3 arm puller, jack, and the large bearing splitter, mm micrometer and mm depth gauge w/articulated mount, correct sealant, and a few other odds and ends. Since a rebuilt t-case is about 1500$, I'm still on the + side by about 800$ including the used T-case w/delivery.

soarvet: yes, tight! I will bend down the body flange and use the shorter guide studs. I just need about 1/4" to 1/2" more room. Just a matter of aligning the output shaft into input shaft and not destroying the input shaft seal.

 

Ashcroft in England is GREAT to deal with. Order placed on may 18th and shipped to my door DHL by May 21! Shim kit and transfer case bearings. WOW!

 

PART 1: Shimming the input shaft bearings. Koyo brand. Keep everything clean. Using a threaded bearing race rod to place the inner race. So the case race goes in first, no shim. The opposite race is in a 'cover.' This cover contains the shims. So the difficulty is measuring the axial play . The input shaft moves around conically when the bearings are not tight in their races. So there is error in the measurement. Measuring carefully while keeping the shaft aligned, and splitting the difference gave me 2.5mm axial travel (2.4 to 2.6mm) without shims. So this is my base shim measurement, and to this I added the .05 preload shim. I put the race with shims into the cover ring and tightened up with three bolts(just use the ones from the brake drum (or somewhere else off the transfer case... they are shorter). Now I checked end play of input shaft and got up to 0.03 play..Now this seems pretty good, but the gear shaft turn very easily...too easily I thought, almost loose.

So I wanted to find the clamping shim, and removed the cover race and removed the .05 shim, placed a .20 shim . Now slowly tightened the cover bolts until the gear tightened. Now it was way too tight, but could be turned with force. The cover bolts were snugged down fairly tightly for this step, but not tight enough to damage the bearings.

So 0.20 mm extra was too much. Then I tried 0.10mm shim, still too easy too turn, and felt somewhat lumpy, like the barrels were still not entirely seating . Then finally, I tried a 0.15 shim. Now this seems perfect, some minor resistance, but smooth to turn, and shaft stops spinning in 1/2 a turn. I think this will be a good preload tension. It feels just like the output shaft gears, which I did not mess with.

I am not using a gasket on the cover holding the race, as this paper gets crushed and thickness changes. Will be using HYLOSIL. The outside cover with get a paper gasket. Shims are not labeled, so you will need a mm micrometer, and a mm dial gauge (that also counts mm's).

TIPS: sandwich the thinnest shims between the thicker shims. Make sure the shims and race seats are spotless before pressing all the way until seated. DO NOT uses a hammer and drift as shown in several videos! Use a press.

So the final shim thickness turned out to be 2.65mm. The original shim was 3.45mm

TOOLS/PARTS:
27pc Universal Press and Pull Sleeve Kit Bush Bearing Removal Insertion Tool Set 100$
Ball joint tool 40$
Three jaw blind race puller 20$
shims, bearings, hylosil , crush spacer, new int shaft nut, OEM shaft seals 170$
Green gasket kit 20$
Used 04 transfer case delivered <300$
Oil/cleaner 50$



pressing inside race with race tool



Pressing on bearing



Measuring end float



About 2.5mm end float



shimming. Had to do this 4 times to get it just right....I think...

 

PART 2: Edited: made a tool from used (37$) tranny output shaft, welded 3/8 22mm socket on end. pull is about 1 lb of pull, turns the shaft..but my scale is from the last century!!. From the internet data I could find, the input shaft torque should be between 1.4 -3.6 kg (but not clear if this is with or without torqued intermediate shaft! One video by Bearmach says the input shaft max is 2.2 Nm (19 lb-force inch) without the intermediate shaft in place ). I'm at 1.3 Nm, cold case, without the intermediate shaft. The next shim size is too tight so I'm good here? This measurement eventually needs to go up an additional 1.25 Nm (11.06 lb force inch..which may have been misstated in one youtube video as 120 in/lbs (12 x in to = foot!)..(because the RAVE says 1.25 Nm = about 10 lb force. inch which has to be converted and maybe was converted 10x too high??!) MORE with the intermediate shaft spacer torqued to correct amount. Have to wait on 150 inch lb torque wrench off ebay (90$)...cost goes up...but I keep the tools!

SOOO: if 1.25Nm == 0.921 lb force foot == 11.06 inch lb force inch added to the input shaft with the intermediate shaft torqued correctly.....will have to see....

Issue being that I could not find a cheap 3/8th Nm dial torque wrench!!!

Hi 360Baby!




not super accurate...but close....

 

Nice work!!! Not sure too many people would take this on as it seems very complex. My compliments to you on your patience and persistence. I have neither!

 

Thx CVH! Its not brain surgery but there is minimal info out there. After shimming the input shaft to a load which maaaaaaybe is OK, then go on to preload the intermediate shaft. So to end metric/ english torque conversions, I bought a sensitive 3 Nm torque wrench. This will settle the debate......

check out this video where the guy adds 120 in/lbs to the intermediate shaft (because he states that the RAVE says "10 ft/lbs" when it really states 10 lbf.in which is pound FORCE - inch!) The recommended 1.25Nm = 11 in/lbs

watch at 20:40


so this is bad info.

but bearmach video gives me some better data but he does it with a less accurate pull string and has to do a bunch of conversions......

at 7:40

You would think he would have a tool like mine and use the torque wrench....

And nothing like clamping the casing to adjust preload on the intermediate shaft. No wonder these things fail.....


Sooooo, in the end I would think that the preload for the input shaft and the intermediate shaft are overall similar; I'm shooting for 1 to 1.5Nm for the input shaft and 1.25Nm for the intermediate shaft.... with total preload for both at 2.25 - 2.5Nm.

 

PART 3: Ok so here is the info I could find on preload for the input shaft and intermediate shaft for the LT230 (Leyland Transmission 230 (230mm between shafts?)). Now some of these are in grams force meters, and some in Nm, and some are slightly different for the same shaft. I also researched the timken engineers handbook, and Koyo or SKF pages too. But there is an art to bearing preload as well as actually finding a bearing in a catalog. Bearing manufacturer numbering system is complicated . There are ways to measure the force needed to turn the shaft. A Nm or ft lb dial gauge, or you could use a gram or ounce pull gauge and measure rolling force. Rolling force has to take into account the radius of the shaft at the measuring point, and is somewhat inaccurate as performed by a hand pull. Timken and others are vague on what exactly is the BEST "minimum bearing load" ie: the preload -- that point where the surface area of the tapered rollers and race are in the best contact to distribute force, but not too loose, and not too tight. Thermal expansion of the aluminum case is different than the steel shafts/gears. So the bearings will loosen a bit before tightening back up. Also, the convergent alignment of both shaft bearings plays a role in how they can absorb radial and axial forces. Too little preload, and the bearings wear as forces are asymmetric. Too much preload, and the bearings wear too quickly as tolerances are again exceeded. Obviously, the type of gear oil plays a huge roll too. Don't want the rollers skipping along or grinding along on the cups....

So although these are basically good strong boxes that take up little room, the assembly of the finer points is within a 'range' and you must learn to try to find the preload 'sweet spot.'

To make life easier, I bought an in lb torque meter and a Nm torque meter. The in lb meter goes to 150 (used military) which is wayyyyy too much for what we need. The Nm meter goes to 0-3Nm, which is perfect. Got it on ebay. So here is the info i used collected from various sources. Output shaft is in neutral.

1) MAX rolling force 350 grams for BOTH the input and the intermediate combined shaft preload measured at the input shaft (bearmach)
2) MAX Nm on input shaft is equal to 1.25 NM PLUS the original input shaft preload( which is never mentioned as a force, just a + shim of 0.05mm) NOT to exceed 3.4Nm MAX total (I don't remember the source..bearmach or ashcroft video?)

3) Old LT230 manual: Input shaft preload : 0.56 - 2.25Nm (5-20in lbs)
4) Old LT230 manual: Intermediate shaft preload: .56 - 1.69 Nm (5-15 in lbs)

5) Max preload on input shaft : 2.2Nm or 224 gram force meter (bearmach)
6) Intermediate shaft preload new manual: 1.25Nm (127 gram force meter) ADDED to the preload on the input shaft (new LT230 manual)

7) Rule: New bearing measurements ARE always tighter (more force to turn) than used bearings
8) I measured ~1Nm on the output shaft (just for an idea of what this was)

So what was my approach? I worked backwards. Using 2.2 Nm as the max for both shafts, I re-shimmed the input shaft bearings until I got a preload of ~0.5 to .7 NM . LUCKILY, I had one additional shim (ashcroft kit) that allowed me to get to this point. I removed a 0.05mm and a 0.10mm shim, and replaced with a 0.2mm shim to get the numbers I wanted. I measured this by turning the Nm dial gauge several times in a smooth easy circle and taking the average of the blue dial marker. I did try to go up another 0.05mm, but this locked the bearing (torque the retainer bolts SLOWLY when you test this). Now here is the kicker! The book and everyone uses axial end play on the input shaft to get the correct shim. BUT, when I measured 0 axial play, and I shimmed the additional 0.05mm, I still had near 0 Nm torque to turn. In fact, even with and additional 0.10 of shims, I still had 0 end play, and almost no force to turn. This may be OK, but I don't think so. I was shooting for about ~0.5Nm preload. So this is close to what I ended up with. It is snug but easy to turn. And of course, no end play. Is it too tight? I don't know...many light truck differentials run around 1Nm but some go as high as 5 Nm.... It depends on the bearing and the forces involved.....

I probably could have added one more 0.01mm shim, but I did not have it (not in the kit)!

I was disappointed to find out that my Hylosil 100 is IVORY color! Not blue or black(the 103 or 4? versions) but oh well.....NOTE: two of the cover bolts go through the case and need sealant at the head/neck. All cover bolts fixed with loctite 290 to 18 ft lbs

 

PART 4: Installed the intermediate gear set. Takes quite a bit of effort to torque the nut to the correct force. Used a long breaker bar. Do not use an impact gun. Once snug (no end play at all), something like 1/16th of a turn gets ~.2 Nm, so GO EASY! I used a large hammer and firmly tapped the end of the breaker bar for fine adjustments. I ended up with a total of 1.8 +/- Nm on the input shaft. This felt fine. All new O rings on the intermediate shaft. Stake the nut when done. A touch of grease on the intermediate shaft bearings to hold them in place while placing the shaft through the holes. Lube all gears and bearings with transaxle lube before measuring torque.....

I think that you definitely need the input shaft tool to do this as correctly as possible.....

So hard part done. Now to get the selectors and switches lined up......

Hope the diff and diff bearings are OK (felt very smooth ). I really did not want to mess with them. Maybe on the spare when I rebuild it.....



18 ft lbs and locktite 290 on the int. shaft lock bolt (little hole)

Hardest part, go SLOWLY!

~ 1.8Nm

 

t-case almost complete. So i'm putting in the switches on the 04. There are 2 diff lock switches(IGM500011 => about 10$ in england!), vs one on my 01, which are the same in function and size. Also, the neutral switch and the HI LOW switch are the same size. All of them 'close' when pressed. The 01 diff lock switch is a different thread size. So the ONLY thing different about all of these switches is the plug on the end . Even the wore colors are similar G/y and G/b.. I plugged off the newer diff lock switch hole (the one where you can't see the switch through the cover plate hole). I will just change the 01 switch and harness connectors to match the 04 version. easy.....

 

Holy crap Most on this forum run away from this repair or upgrade. Pretty hefty stuff