H151F synchros I presume

[jcolvin]

My H151F doesn't like to shift into 2nd until it has warmed up, and won't go back into 1st unless you come to a complete stop or let your foot off the clutch a little.

Am I correct in thinking it's probably synchros I need? I presume this is not typical H151F behaviour? I'd like to order the parts *before* we pull the tranny apart.

 

[roscoFJ73]

Its pretty normal for big gearboxes to be like that in the morning or has it gotten worse lately?
Thinner oil can help. Maybe its clutch related

Do you use 1st for take off all the time? I always use 2nd unless its on a steep hill.
All the H55f are hard to change from 1st to 2nd and back when cold or over about 10kph.

 

[jcolvin]

Its pretty normal for big gearboxes to be like that in the morning or has it gotten worse lately?
Thinner oil can help. Maybe its clutch related

Do you use 1st for take off all the time? I always use 2nd unless its on a steep hill.
All the H55f are hard to change from 1st to 2nd and back when cold or over about 10kph.

Well perhaps its just normal behaviour. I haven't driven any other H151F before. Once it warms up it certainly behaves better. Clutch seems to work fine, I don't think it is dragging. When it is cold it is a bastard tho.

 

[lshobie]

I have a 151 here, it's stiff when cold - minus 10 and lower. First gear is pretty low on them and is hard to go to first from second. Not wanting to go to 2nd from first is usually a sign of wear and higher kms, but I have also noticed the same tendancies on other toyota trannies from 1st to second - and they don't all have higher kms - maybe just poor maint by previous owner?

Like Ross said - try a thinner fluid - maybe a synthetic.

Regards,

 

[jcolvin]

I have a 151 here, it's stiff when cold - minus 10 and lower. First gear is pretty low on them and is hard to go to first from second. Not wanting to go to 2nd from first is usually a sign of wear and higher kms, but I have also noticed the same tendancies on other toyota trannies from 1st to second - and they don't all have higher kms - maybe just poor maint by previous owner?

Like Ross said - try a thinner fluid - maybe a synthetic.

Regards,

Hmm. It only has 125,000 km on it, so shouldn't be worn yet. I put fully synth amsoil severe gear 75w90 in it, perhaps this is too viscous?

 

[bigbrowndog]

Hmm. It only has 125,000 km on it, so shouldn't be worn yet. I put fully synth amsoil severe gear 75w90 in it, perhaps this is too viscous?

They are all the same here in the tropics, my 80 is like that also. This gearbox needs the synthetic oil and a lighter grade than what you are using as I cannot relate to the temperatures you guys operate in Canada. I changed to synthetic but could not get a lower viscosity oil with out ordering it from the south. It did make a difference but not a great deal, a lower viscosity oil would be better even here and the synthetic gear oil should give better protection. Far better gearbox to shift when warm than the H55F, LOL. So mine will suffer until summer is finished. cheers.

 

[roscoFJ73]

Hmm. It only has 125,000 km on it, so shouldn't be worn yet. I put fully synth amsoil severe gear 75w90 in it, perhaps this is too viscous?

If your box is quiet and changing the other gears ok,I would leave it.
Try the 2nd gear takeoffs,even a 1HZ has torque enough to chug away without laboring