4W305 tranny/dropbox Issue

We have a 4W 305, Person who Sold it to us gave us a line of things he had done to the tractor, None of it was true. There are inner bearings on the Hydraulic pump drive, We had a wine when driving and using ours. But while you are into that you need to checkout gears and other bearings in Transmission. We only had to rebuild everything on the Hydraulic side and our issue went away. We also had to put in a rear engine seal, the man we bought it from put it in backwards, We are not set up to do work on tractors of that size, So parts were available and I thought reasonable, But the Labor bill was large. With everything we spent over $20,000 and we hauled the tractor to and from. With all of that said, We need to paint ours but we have a solid tractor now that we pull a 30" 1 pass tool with, And we use it on the grain cart because it sits up high enough to see over the top of a semi trailer. NO def fluid and way cheaper than a new tractor.

Yes sorry I didn't state that,it does have steering as well.

Thx Mark

You have to remove the rear housing from the dropbox to get the hyd drive out,

Oldred wrote: Hello fella's, Got a line on a 4W305 as a repair project. The issue is that it wont move. It has all hydraulics and the pto shaft is turning but when put in any gear there is a slight grinding sound coming from between transmission and drop box. Question #1: Is there a coupler between transmission and dropbox ? If so is a replacement available ? Question #2: What is the procedure to disassemble as I don't have a service manual for that model ? I'm guessing remove cab and pull engine/split tractor ? Thanks for any info or advise prior to committing to this unit. Mark Laczo Alberta Canada

Hi Mark. I hope I am in time to help with your questions. I think maybe we have talked before as I have had a few different Allis tractors for a long time. I am over north of Camrose so not too far apart.

I had the splined coupler fail on my 8550 once during harvest and had the grinding noise and no ground drive but everything else worked. A quick temporary fix was to remove the back slab off the drop box that has the pump drives and PTO in it. I was able to pull the worn out coupler out the back then and replace it without a major rebuild. A year or two later I did a major rebuild on the transmission and drop box when I did the 855 Cummins repower. There is no oiling to that big coupler and the splines on the output shaft of the trans and the input shaft of the drop box will wear some and it depends which is worn the most whether a new coupler will get you going or not. When we did the big rebuild we did some calculation of pressurized oil flow to the 5 or 6 different places in the main transmission that get a specific number of gallons per minute of flow. The service manual which I have, shows how many GPM each location gets and we made the call that out of 16 ?? gpm in total that we could drill an orifice in the seal that keeps pressure oil inside the hollow main trans output shaft and the live shaft that runs inside it and powers the rear main housing for hydraulics, pressure lube and pto. I think we determined that about a 1/16" orifice would allow about 1 gpm to flow out the rear of the hollow main shaft and lube the splines there to prevent them from wearing out. Seems to have worked so far!

I also think we had a machine shop rebuild the splines on the drop box input shaft for a tight fit with the new coupler. At the time we were able to get a new trans main shaft.

I have all the replaced parts yet and the service manual so if you want some help with your potential project call me at 780 662 2614. I always enjoy talking about old orange iron!

I have some pics of the main shaft and coupler if you want to see them. I can't load them to this site because file size is too big and Photobucket doesn't work any more. Send me your email if you want some pics.

After reading the posts again, esp the one from Amos, we made engine stands with rollers on the bottom like you talk about. We did not take the cab off though. I think we used a transmission jack and rolled the trans and drop box out the front. I don't know which would be easier but with the engine out what we did worked pretty well.