coaster gearbox

exa41 · Guru

coaster gearbox

Aus-Kiwi · Guru

Check with Dellow.com.au if you want to upgrade to auto? They make bellhousing to adapt gearboxes or auto..
I suggest they are fitting the weaker version of your gearbox ??
Another thought ? Check the oil or trans oil used.. We had an Isuzu years ago.. Looked after it by changing oil with what we thought was the right oil . As it said gear box oil !! They run a LIGHT oil and I'd too thick and short distances it doesn't get to lube the fine needle bearings.. Check .. Some Jap trans use engine oil..

exa41 · Guru

I had a box recoed by mr coaster , and they specified the oil to be used , If I had knows about the weakness of the box in general I would have upgraded it then,

mr glassies · Guru

sounds like a bad rebuild . any warranty

dibs

exa41 · Guru

Yep warranty was for 6 months 9 months ago , not a good outcome.

Blue · Senior Member

should be using just an 80W90 oil....

you'd only go a bit lighter if the gears are real sticky...

we have coasters in our company mid 90s and onwards... over 400,000 on them and never had any trouble with the boxes... :)

Murraman · Senior Member

The one in our 85 bus is an 83 box and from what I have been told is original with 350k on it. The one we had in originally had 2 crook syncros and it only had 160k on it.

Personally I think you got dudded by a bad rebuild. If the original lasted x k's over 30 years then a rebuild lasts just over 12 months, Me thinks you were ripped off and I would be jumping up and down.

You are the first coaster owner I have spoken to or seen on a forum who complained about a weak gearbox, So I think you maybe unlucky.

exa41 · Guru

HIi Murraman , I cant understand it either , I have had the camper for 18 years now , the speedo says 265,000 and the odometer never worked for 10 years so the original gearbox IMO did really well. Towed my race car in a tandem trailer all over Aust and never gave a hint of a problem . then I retired and decided to go on a trip and its broken twice and I hear what you are saying about a dud rebuild ( I was thinking that myself) The problem is they say the Holden 308 that's in front of the box but it doesn`t produce much more torque than a good diesel so I passed that idea bye . Must be the retirement thing and bad luck , or poor management ,or both who knows .

mr glassies · Guru

what acutely broke Dennis can see a ****ty old holden screwing a diesel box and iv seen heaps of implants .
blue i ran a thicker oil in one of my truck boxes and it caused 2nd sincro to opt out my gearbox guy said it was because the thicker oil was harder to squeeze out of the sincro cones i can see what he means i suppose .

my 2 bobs worth hehe

dibs

exa41 · Guru

Last time it took 2 teeth of the input shaft which made every other damn thing noisy , this time its the same noise so I presume that it is the same . The oil I put in the box was rated at GD5 75/90 ( pretty sure ) which is what the guy in Seymour for Mr Coaster told me to run ? The box use to change lovely most of the time , if I didn`t get it right 2nd and 5th were hard to get at times but if you didn`t hesitate it was OK . Problem was it was only guaranteed for 6 months and with the health issues that I have had , we haven't gone away very much , the gearbox guy recons that its the 308 but I recon that's crap but unfortunately his say goes and he was the only one that had a gearbox.

Jaahn · Guru

Hi exa41,

My experience is a bit old but there were lots of different boxes fitted to the Coasters and the Dynas in the 70-80s.They were continually changing them and different engines had different types. Not usually prone to giving problems if they don't run out of oil. However breaking off teeth is usually either a fatigue problem or there are other bits floating around and taking the teeth with them. Its a short time to destroy the box if a bit breaks and gets carried around between the teeth. disbelief

However the six cylinder engines had a heavier box and similar to the "cruiser box. That would be the one to go for. The Dyna trucks had the same boxes too as said already. There would be some minor changes to accomodate if you change boxes so try and get access to the whole vehicle to make it easier. confuse

good luck jaahn smile