12HT H55F running Hot. (1 Viewer)

Joined
Mar 30, 2008
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South Africa- JHB
HI,
the Gearbox in my HJ61 runs very hot. it gets warm within a few minutes and then just keeps getting hotter. Eventually it gets to the point where the heat travels up the gear lever. the boot is also hot. i can touch it, it does not burn me but it is still hotter than any of my other 60's and 62's.
this is my first diesel cruiser, do the G/boxes run hot in the diesel?
i have recently had an entire G/box and T/case over haul, new gears and bearings as well as seals. oil levels are where they should be.

any ideas? is it possible for the G/box to be out of alignment?? ie bent or sitting scew??
 
Joined
Sep 3, 2007
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Longmont, CO
 
 
HI,
the Gearbox in my HJ61 runs very hot. it gets warm within a few minutes and then just keeps getting hotter. Eventually it gets to the point where the heat travels up the gear lever. the boot is also hot. i can touch it, it does not burn me but it is still hotter than any of my other 60's and 62's.
this is my first diesel cruiser, do the G/boxes run hot in the diesel?
i have recently had an entire G/box and T/case over haul, new gears and bearings as well as seals. oil levels are where they should be.

any ideas? is it possible for the G/box to be out of alignment?? ie bent or sitting scew??
I wouldn't say its a "diesel" thing for the gearboxes to get any hotter than a gasser. Warm is typical, and expected, however.

Sounds like the rebuilt has made everything tight. Maybe the bearings are just new. Maybe some preload was set wrong. Keep an eye on it, I guess.

I typically do not feel any heat in the shifter of my H55s.
 
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Joined
Dec 16, 2010
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517
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The Northern of Va.
Ive never had a manual transmission that after long drives hasnt been warm at the bottom of the shifter. Gears are spinning and there will be heat and since the shifter is riding on top of the gearbox, youre bound to feel some temperature. How much fluid is in the box and how old is it?
 
Joined
Dec 6, 2006
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Nova Scotia, Canada
hit the tranny & t-case with a temp gun after you run for a bit. See what kind of temperatures you are getting. I would change the oil in both and check for filings / metallic sheen, but that is just me being paranoid. Generally after a rebuild you should be changing the oil after a few 1000km because new parts are being worn in. Fill the tranny through the shifter opening at the top of the tranny, it is a lot easier than the side plug.
 
Joined
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Richmond B.C.
 
 
My 61 ran warmer on the base of the shifter more than compaered to my 62 but then that tranny toasted itself months ago have another one in but have not noticed if it warms up the same.
 
Joined
Jun 1, 2006
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Port Coquitlam
 
 
Mine (3B, H55) on longer highway hauls in the summer warms up a bit, I can touch the bottom of the shifter and feel a little warmth but by no means would I say it's running hot. If all the bearings that need a preload on them were not set up properly it would create friction, stress, added resistance and would cause the system to run hotter.
Check the temps with a temperature gun ( the laser ones work well) in several spots, check the top of the transmission, bottom, the transfer case, see if the readings are all the same or one is running hotter than another. Check your oil, does it smell burnt, does it look much darker than new? has it been changed since the rebuild? Have you noticed a decrease in power when driving, any new noises, vibrations?
 
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South Africa- JHB
ok, will check the temps. before the rebuild, it also ran hot. i have a thread on here that explains what happened when the box "gave up" ripped the oil receiver right off and sent it through the Idler gear in T/case....
Fantom, there is a high pitch "whining" sound when at cruising speeds, sometimes it louder than others and sometimes not there.... i had a FJ45 that made the same sound and that box lasted years.... eventuall sold the vehicle and its still running with the sound.

the heat i experience after a while gets to the point when i can touch but it does let you know that its hot! almost uncomfortable hot. if that makes sense??

i have not changed the oil, its done about 2000km since box and t/case rebuild.
 
Joined
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South Africa- JHB
ok, will check the temps. before the rebuild, it also ran hot. i have a thread on here that explains what happened when the box "gave up" ripped the oil receiver right off and sent it through the Idler gear in T/case....
Fantom, there is a high pitch "whining" sound when at cruising speeds, sometimes it louder than others and sometimes not there.... i had a FJ45 that made the same sound and that box lasted years.... eventuall sold the vehicle and its still running with the sound.

the heat i experience after a while gets to the point when i can touch but it does let you know that its hot! almost uncomfortable hot. if that makes sense??

i have not changed the oil, its done about 2000km since box and t/case rebuild.
 
Joined
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The Northern of Va.
the heat i experience after a while gets to the point when i can touch but it does let you know that its hot! almost uncomfortable hot. if that makes sense??

i have not changed the oil, its done about 2000km since box and t/case rebuild.
Wow, I always get some warmth but never that hot.
 
Joined
Dec 6, 2006
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Nova Scotia, Canada
Change oil for sure ! You have some decent temps there in Joburg. Wish it was that warm here in Eastern Canada. Next time I go for a decent run I'll get my temp readings. If I remember correctly the last time I drove across Canada I kept an eye on my t-case temps (at rear of case) and they ran in the 125 deg C range.

What kind of gear oil are you using?
 
Joined
Nov 23, 2008
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Richmond B.C.
 
 
Does the whine go away when you press in the clutch mine also whines but I know its the throw out bearing also my boot is not fastened down at the moment so it sounds louder than when the boot is bolted down.
 
Joined
Jun 1, 2006
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if it ran hot before the rebuild and it does again after there may be another issue causing it. Change the oil, especially after a rebuild you should around 1000-2000kms just to see if there are any shavings and to make sure everything is aligned properly. Once you get the temp readings let us know, as for the noise, some transmissions make a whiny noise, depending on the truck and insulation in the floor you notice it more or less. Is the noise directly related to the RPM? or the speed? do you notice it only under load? or even coasting? is it more pronounced during downshifting or up hill acceleration when you have larger stress?
Mine whines a bit during driving in all the gears but that is more of a mechanical gear noise and due to the transmission being as old as the rest of the truck (normal wear over 533,000kms).
 
Joined
Mar 30, 2008
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South Africa- JHB
Dieseler, yes the noise does go away once clutch is in. the noise is intermittent and only comes in at about 90-100km/h. under load and just coasting in gear...
i also have a bad vibration on my propshaft, from about 80km/h on ward it vibrates hard, but when i release the accelerator pedal it smoothens out nicely... i can then "nurse" the power pedal and the vibration goes away untill i press the pedal hard again. could this be contributing to the heat.

i noticed yesterday, if i drive between 85-95km/h the box gets warm, but anything over that, it started getting Hot... i dont go over 115km/h, not because of the heat, but because i just dont want to...
 
Joined
Nov 23, 2008
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After having a countershaft bearing self destruct then replacing it only to have the countershaft teeth drop off the shaftgear months later I lean in that direction but I think there are more members that have way more knowledge and experience on these issues than I do.
 
Joined
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Nova Scotia, Canada
Check to make sure all your prop shaft flange bolts are tight and torqued properly. Also check for play at the output flange of t-case and input flange of rear diff. Check your universal joints and make sure everything is greased, including axial grease nipple for prop shaft. Vibrations = bad and will rip everything apart quickly. Your descriptions tells me it is loose bolts. If it was bad bearings usually the vibration disappears when components have load and vibrates with no load.

Is there a lot of play or clunking when you are hard on the accelerator then release quickly to decelerate?

As for your whine, the better the descriptions the easier to diagnose. If you push your clutch in slightly and it goes away then likely throw-out bearing. Although I have found the throw-out bearing tends to squeek, not whine. Get it to make noise, keep load on tranny, and push clutch in ~1-inch. If it goes away then it is throw out bearing. I suspect it is something else. Gears tend to whine.

Your oil will tell you everything !

Good Luck
 
Joined
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South Africa- JHB
Ben-jammin,
i will check the props and grease them.
as the whine starts, its actually more of a whistle, its NOT the turbo whistle :). its a VERY high pitch (Almost sounds like singing) and does go away if i touch the clutch, even one inch. that is why im not so sure its gears as they are turning because the wheels are turning, right? if it were the gears it would be a constant noise... i also find that when its whining, i can press the clutch in a few times (pump it) and the noise goes away if i hold the speed constant... if i accelerate there is no noise untill i back off and just cruiser... the whine returns...
 
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Nova Scotia, Canada
Throw out bearing for sure. My Fix --> crank up the stereo! Did they not replace the pilot & throw-out bearing when you had yor rebuild on running gear? You are 7/8th of the way there anyhow. Maybe it was in good shape. Regardless, nothing to worry about. Change your oils and be happy your driving a Cruiser !
 
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vancouver B.C. Canada
For you HJ61 H55f guys anytime you pull the clutch or gearbox ALWAYS ,ALWAYS replace the throwout bearing. No more cricket sounds!

NEG NEG what viscosity gear oil are you using
 

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