Volvo 4400 Trans

[antz]

Hello all,
Im currently working out what I should do with my loader. Transmission is looking like it needs a rebuild. Other that oil leaks, the rest of the machine seems to be ok. Pins are tight and it is in good condition for the 40 odd years it has been in existence.

I have the following options:

1. Rebuild my transmission in my own time, noting I have never pulled one apart. Parts seem available and probably around 5k (Australia) plus my labour. I have workshop manuals and reasonable mechanical ability. Most parts will come from Turkey - Volvo genuine NLA or outrageous in price.

2. Run the loader as it is and put up with it dropping out of gear when it gets hot after half hour. Dangerous on the farm.

3. Send the machine to the auctions and get what I get for it. Look for a replacement and take the risk that it will have major problems. Minimum replacement cost 25k.

4. Swap the transmission. I have located a trans from an L90. The guy wrecking it assures me that it will fit into my loader - he is somewhat of a Volvo guru. This is contrary to other advice and research I have done. I was of the understanding that the HT100 was only ever in the 4300 & 4400. He is asking 7k but it is without any sort of warranty. Apparently in 'working condition' when removed from the L90. Dropbox is toast so I would need to use mine, and I am again dubious about this fitting the L90 trans.

It is very difficult to get information about a machine of this vintage here in Aus let alone parts. The guys that would know much about them have long retired and younger people laugh when I tell them the model and have NFI. Im currently about 15k deep in purchase price and parts. Have owned machine for about 5 years.

Information and thoughts, particularly relating to fitment of the L90 trans appreciated.

Thanks

 

[sfrs4]

As far as I know, the 4400 and L90 transmissions aren't the same, BUT that is based on part number cross referencing, it could well be that your man has knowledge that the input and output are the same with the bolt holes being the same to bolt it into place but again the part numbers don't match up so who knows, it could well be that it will bolt into place and your gearing might be slightly different but it will work.
Repairing yours, there are plenty of A/m suppliers else where in the world before scraping the barrel with Turkish parts, please leave that as a last resort.
There are multiple suppliers in Sweden and Europe who can help. BUT I'd get a complete list together of the parts you need first, and source them. I have seen this with customers before where they start into a piece of older equipment buying bits as and when they find them broken, only to find a few months down the line a crucial part is no longer available from anywhere and they are stuck thousands of $ into a now huge paperweight.

 

[antz]

As far as I know, the 4400 and L90 transmissions aren't the same, BUT that is based on part number cross referencing, it could well be that your man has knowledge that the input and output are the same with the bolt holes being the same to bolt it into place but again the part numbers don't match up so who knows, it could well be that it will bolt into place and your gearing might be slightly different but it will work.
Repairing yours, there are plenty of A/m suppliers else where in the world before scraping the barrel with Turkish parts, please leave that as a last resort.
There are multiple suppliers in Sweden and Europe who can help. BUT I'd get a complete list together of the parts you need first, and source them. I have seen this with customers before where they start into a piece of older equipment buying bits as and when they find them broken, only to find a few months down the line a crucial part is no longer available from anywhere and they are stuck thousands of $ into a now huge paperweight.

I have used other suppliers, it is just that the pricing of getting parts here in aus is borderline extortion, in particular if I have to pay in Euro. The few turkish parts i have purchased have seemed ok quality wise, and the service and freight has been fantastic. I am trying to put a part list together as there doesn't seem to be a 'kit' as such.
Regarding the transmission interchangeability, looking at the diagrams for both they look the same however that doesn't mean a whole lot. The L90 and the 4400 also both ran the same engine but that doesn't mean the bell housing is the same or the drop ox will bolt up. I am leaning toward rebuilding my trans. At least then I will know that it is good. I could purchase a second hand one and be stuck in the same position. Can I ask what the issue is with parts from Turkey?

 

[sfrs4]

We dealt with, DEALT with, don't anymore, a couple of suppliers from Turkey, their quality control is at best questionable, and quality of the steel for steel parts is also very questionable. their ability to copy stuff is amazing and they are producing copy parts at a phenomenal rate, but, I believe their tooling is the problem, they will use one machine with one bit of tooling, so the first so many will be brilliant copy's, after that the tooling starts to wear and discrepancy's start to appear, tolerances start to disappear etc. After an increasing rate of faulty parts and slow/unreliable shipping we gave up using them as suppliers as we couldn't trust the products.
If you can get all the parts, I think you are correct about rebuilding, it's better the devil you know than the devil you don't. but just try to find better, have you used a UK company yet? I thought our exchange rate and trade deals meant better deals to be had, I know we have had a couple or more auz and nz customers.

 

[antz]

We dealt with, DEALT with, don't anymore, a couple of suppliers from Turkey, their quality control is at best questionable, and quality of the steel for steel parts is also very questionable. their ability to copy stuff is amazing and they are producing copy parts at a phenomenal rate, but, I believe their tooling is the problem, they will use one machine with one bit of tooling, so the first so many will be brilliant copy's, after that the tooling starts to wear and discrepancy's start to appear, tolerances start to disappear etc. After an increasing rate of faulty parts and slow/unreliable shipping we gave up using them as suppliers as we couldn't trust the products.
If you can get all the parts, I think you are correct about rebuilding, it's better the devil you know than the devil you don't. but just try to find better, have you used a UK company yet? I thought our exchange rate and trade deals meant better deals to be had, I know we have had a couple or more auz and nz customers.

Hmm fair enough. I havent looked at any uk suppliers. Happy to look if you can point me in the right direction. I have in the past emailed a few places that were breaking machines but never got a response.

 

[sfrs4]

I have sent you a message.

 

[antz]

Would it stand to reason that if an L90 transmission does bolt up to the td60 engine, any of the HT131 transmissions would bolt up, L90c for example? It significantly expands my options.

 

[sfrs4]

I can't see why not, BUT bolting up and working are two different things, you may have different gearing, different sensors, different plumbing etc, it is half the battle getting them to bolt up... the old adage of with enough time and money anything is possible comes to mind.

 

[antz]

I just thought I would post an update as it annoys me when people don't follow up on threads.

This is my diagnosis so far:
It seems that the fwd / rev bearing has failed on the oil distributor end, and this has increased the wear unevenly on the oil distributor housing and that would allow significant leakage. It is difficult to see the uneven wear in the below photos but very obvious when you have the oil distributor in the hand. The shaft also has at least 1mm of play when moved by hand. It is also obvious to me that the oil distributor has had additional shims installed to space it out from the shaft seals further because of the wear in the housing from the seals - there are two obvious sets of wear marks / grooves about 1mm apart.

Next step is transmission removal.

 

[antz]

Just a progress post.

After removing the transmission and tearing it down, it became obvious to me that it was going to be difficult to justify a rebuild. I only pulled the fwd/reverse shaft right back to bare bones but that alone was enough to make the decision not to rebuild. It seems obvious to me the someone has been in there before. The shaft has some damage from being dismantled before as well as a fair amount of wear. Clutch plates and friction discs looked fine. The 3 oil distributors / manifolds have grooves worn in them and are unavailable for purchase. With enough time and money all these parts can be repaired I think but neither of these are on my side.
I purchased a ht131 that I believe came from an L90D. I replaced a couple of gaskets as well as the three piston seals between the fwd/reverse oil distributor / manifold and also the large o-ring between the flywheel housing and the transmission. I got the new trans into the machine a few days ago. Next will be the drop box then the brake boosters, drive shafts etc.

From what I can tell, the HT131 looks to be an evolution of the HT120. The casing looks to be the same however there are quite a few differences with the ancillaries. The newer trans has some extra lubrication lines running around the place, a completely different torque convertor (much much smaller), and the clutch shafts are much bigger in diameter. There is also some wiring changes, the solenoids appear to be oil cooled as well. Fingers crossed the drop box fits up ok.
I need to work out what oil the new transmission takes. All the information that I can find suggests 10w/40 or similar but it quite obviously had red ATF in it before i got hold of it.

 

[sfrs4]

Volvo's service sheet for the L90D says Volvo VDS3 which is engine oil , 15w 40 or 10w 40. glad it's going ok so far, fingers crossed for the rest for you.

 

[antz]

Here is a bit of a summary:

HT100 to HT131 Transmission Swap – 4400/4300


Removed the transmission. not a fun job. It took just over a day for two people. Once pulled apart, I found damage and wear to the fwd/rev clutch shaft, and with some parts no longer available, it wasn't economical to repair. Sourced an HT131 from an L90D as the replacement - $6000 AUD approx. Hours unknown (apparently 6000 but who knows)


Installation took around 3 hours and it bolted up to the engine without issue. My existing drop box fitted fine as well. There are a few differences to the old transmission - some additional lubrication lines and different solenoid wiring but the housing looks to be identical. The internals appear to be different and I don't think you could interchange parts between the two, for example the shafts are bigger diameter on the HT131.


For anyone who has the misfortune of doing this swap on a 4400 or 4300 (HT100 to HT131), here's a few challenges that I had to overcome:


Cooler Lines - The transmission cooler lines need adapting. I ended up using a combination of fittings from both transmissions and had to weld two fittings together to make it work.


Lubrication Line - There is an oil line that runs from the front of the transmission, picks up the oil cooler port on the right hand side of the trans, and goes to the back of the PTOs/pump drives. My 4400 only runs one PTO pump and doesn't have the lubrication line on the back of the PTO housing, so I fabricated a new line from steel tubing running from the front of the transmission to the cooler boss on the side of the trans. Referring to the parts diagram for both transmissions will give clarity on this.


Solenoid Wiring - The solenoid loom is different. I had already replaced the loom on my loader and terminated it to a Deutsch plug. The HT131 came with a small piece of harness, so I patched a Deutsch plug onto that to match.


Sensors - A combination of temperature and pressure sensors from both transmissions are needed. There are wiring differences here too but nothing difficult to sort out.


Plugging Ports - I removed all the remote pressure test lines and installed plugs. If pressure testing is needed later, there's room to swap in test fittings (I think I will burn the thing before I spend any more time on it). There are also a few oil ports that needed to be blocked that the 4400 doesn't require, additional sensors etc.


Lifting Frame - I highly recommend following the Volvo service manual removal procedure, including fabricating the lifting frame that straddles the seat hole and the engine. I fabricated the frame after pulling the transmission but before installing the new one. It would have been much much easier if I had used this from the start. Between the diagram in the back of the manual and a tape measure it isn't difficult to make this from some scrap. Some steps in the procedure don't seem worth doing at the time but pay off later with one exception: I did not remove the hydraulic pump. Instead, I unbolted the PTO drive from the transmission and left the pump hanging by a strap and the hydraulic tank.

Dipstick / Filler Tubes - I damaged the trans filler tube by not disconnecting it fully. The replacement transmission did not come with one either so i had to cut / weld / repair the old one including replacing the olive. After manufacturing a section of pipe to replace the damaged section I realised that this is a standard hydraulic tube size and I ended up getting a small piece from my local hydraulic supplier. Reading the service manual correctly could have prevented this. Not having the lifting frame is also partly to blame.


If doing this again (touch wood never) I would pull the engine and transmission out of the machine together. There's a lot of cleaning that would be much easier with everything out, and bolting the engine and transmission together outside the machine would be far easier than doing it in situ. The transmission seals into the engine with an O-ring which makes it a very snug fit and requires a lot of swearing if the alignment isn't perfect. There are a couple of other issues that I created, including snapping the dump pipe off the turbo and pulling the air filter to turbo pipe off when the engine was unsupported without the transmission in holding it up. I think time wise it probably would work out the same to pull the engine and trans together or just the transmission. I did also replace the piston seals on the manifold / oil distributior that is under the seat. These are cheap and whilst they can be done later with removal of the seat they are much easier to do with the transmission out of the loader.


I have fitted a new seat and gave the machine a good workout for an hour yesterday. Everything seems to be fine. It pulls much harder than before and is far more willing. Has a real spring in its step now. Unsure if the new torque convertor has anything to do with that. Now to get the brakes working and then onto replacing the 3 leaking hub seals

 

[Welder Dave]

Glad it works after all the work you did on it.

 

[sfrs4]

for those that may come along in the future, thank you for the write up and helpful information, I am sure at least one or two people will come across this in the future and think, if he's done it and it works I'll give it a go, especially as that era of Volvo loader will more than likely out live their younger counter parts

 

[antz]

I am now having problems with the dropbox getting filled with oil from the transmission at a very rapid rate. Any one have any ideas on why this might happen? My only thought is that one or both of the seals on the drop box side of the transmission are leaking or missing. It will overfill the drop box in a couple of minutes at idle. I hope I can change these seals only removing the drop box and not the transmission as well. Would be seals 11 & 17 in the diagram.

 

[sfrs4]

For the life of me I cant figure out what is going through, or what cap is on the third hole between the two mentioned, I assume there must be a seal there as well
you might want to look at getting O-rings 12 and 18 while your in there.

 

[antz]

I will try to find the best diagram that I can, but I am pretty sure the drop box only has the two shafts going into it from the transmission so I cant see it leaking from anywhere else.