3320 Stability Woes

orlo · Feb 13, 2009

Hi:

I had a 3320 Open and now have a 3720 cab (Read even tippier). If you ballast it properly and load the tires (or use wheel weights) it feels pretty stable compared to without it. I have an 1100lb ballast box that I use whenever I use the loader for anything substantial.

I also put 6" (6" per wheel, 12" overall) Unverferth wheel spacers on it. I'm now running 66" wide in the narrow position (I'd add about 5" for a little over 71" if I went to the wide position). I'm running that with R3's and it's pretty stable, certainly much more than when I first got it. When I first got it I had unloaded large R4's and with an 800lb stump grinder (long with extra leverage) it would still lift the rear end easily and I was up on 1 wheel once (Read super-duper pucker factor) when using the 72" grapple with a long tree that was heavier on one side.

Conservation · Feb 13, 2009

The argument for adding rear ballast cannot be overstated. However, I am concerned about the accuracy of saying that adding rear ballast reduces the stress on the front end. Unless the ballast is added considerably behind the rear wheels, the load on the front remains the same. The percentage front and rear of course changes, but that is only because of the rear change. There is no front change. If the rear of the tractor rises considerably, then of course there would be weight transfer to the front.

JDGREEN4ME · Feb 13, 2009

orlo said:
Hi:

I had a 3320 Open and now have a 3720 cab (Read even tippier). If you ballast it properly and load the tires (or use wheel weights) it feels pretty stable compared to without it. I have an 1100lb ballast box that I use whenever I use the loader for anything substantial.

I also put 6" (6" per wheel, 12" overall) Unverferth wheel spacers on it. I'm now running 66" wide in the narrow position (I'd add about 5" for a little over 71" if I went to the wide position). I'm running that with R3's and it's pretty stable, certainly much more than when I first got it. When I first got it I had unloaded large R4's and with an 800lb stump grinder (long with extra leverage) it would still lift the rear end easily and I was up on 1 wheel once (Read super-duper pucker factor) when using the 72" grapple with a long tree that was heavier on one side.

Will these spacers create additional stress on the rear axles? I know I am interested in the 3000 Series tractors and this issue is of concern to me. I also thought of going with the smaller size R4s to help lower COG...if that would even make a difference.

bluemalibu · Feb 13, 2009

Thanks so much for all of the suggestions offered... and a big thank you to Rick for the in-depth PM help!

Conservation · Feb 13, 2009

JDGREEN4ME said:
Will these spacers create additional stress on the rear axles? I know I am interested in the 3000 Series tractors and this issue is of concern to me. I also thought of going with the smaller size R4s to help lower COG...if that would even make a difference.

I'm not an expert on that model, but yes it will. Anytime the acting force is moved outward from the supporting bearing, a moment, or twist occurs. The thing I don't know is if this would be anything to worry about on this model. Many are built so robustly that you can get away with the extra load.

SFish · Feb 13, 2009

I have a 3320 and can't add much to the excellent advice above. I have all R4 tires turned out and filled and have a heavy 6' Gearmore box blade or 447 backhoe on the rear most of the time, and I am pleased with the performance on my very hilly terrain. The backhoe is most usefull when working on a side hill because I can extend the boom far out to the uphill side to insure good balance. Most of the times that I have had a rear tire lift is when carrying a heavy log with the loader/grapple that I grabbed off balance. Weight it down and go slow. Steve

Nuru · Feb 14, 2009

I solved my stability concerns with the install of a set of Turf specials. I have slopes on my property and they range from as steep as 15 - 25 degrees, and I have been on all of them. I also have a MMM, and I know that also helps. The Turf specials work, but I know when I installed my blade this year and put my dirt scoop on the back, my stability went way up, and the dirt scoop wasn't even filled with anything substantial (300 pounds of ice melt and salt). This year I will run my loader with the ballast box on and my MMM. I toyed with the idea of spacers (6 inchers from Unverferth), but sofar I have not yet bit on them. But who knows, I might in the future.

Millalien · Feb 15, 2009

I've got a 3320 and would only add that the tilt-meter accessory helps with my mental health - it really helps calibrate what feels tippy to where I might be relative to an actual tipping point. There's many ways that the little meter is wrong, but it's still been a useful reference point for me, especially when the machine was new.

I have hilly terrain with +15 slopes, R4s filled, usually a BH and grapple bucket, and I keep everything down low and go slow slow slow. I'm thinking about adding spacers and/or wheel weights this spring as well.

plastikosmd · Feb 15, 2009

As above, I never use the loader without weight. Backhoe in the summer and weight box in the winter. My tires are not filled. The reason I bought this machine was the size and the CX power. With only the weight box, I just picked up a small mead speedcat crawler and put it the back of a guys trailer. He looked at me when I chained/hung it from the bucket and said no way. In she went.

orlo · Feb 15, 2009

JDGREEN4ME said:
Will these spacers create additional stress on the rear axles? I know I am interested in the 3000 Series tractors and this issue is of concern to me. I also thought of going with the smaller size R4s to help lower COG...if that would even make a difference.

Technically Yes, but also keep in mind that the max width with R1's is 68.4 (Very wide, wider than I am now at 66) so I'm not exceeding the designed or factory setup maximum width.

It's the outer edge of the tire (width) that counts. Now if I flipped the wheels with the spacers for 72" I'd be a little over but not by much.

Why they don't offer the 8 position wheels with R4's is beyond me. You only get 1.6" of width gain when flipping them (R4's) and I think they are not very wide in the wide position. The R3's offer 5" of difference narrow to wide. The R1's offer about 16" (52.4 - 68.4) narrow to wide. The big R4's offer only 1.6" (58.1 - 59.7" wide). The smaller R4's only go 57.3 - 58.9. Again, I'm not sure why they don't offer the 8 pos wheels with the R3's and R4's, would make things a lot easier. I don't hear many folks with R1's in the wide position complaining about stability.

One thing about going wide is you'll be wider than the 63" bucket and the 59" blower. I haven't found this to be an issue. The extra width very rarely is an issue and the stability it provides is well worth it.

The dealer put mine on and I didn't void my warranty or anything. Note that We also flipped the front wheels also.

One note also about filling tires. You may find that you like the 'stability' better but in my opinion (I rode with empty/full tires on my 3320 and 3720 - Filled now) filling them does make the ride quality (shock absorption) crappier. It makes sense since due to the reduced air volume (say 90% less) any distortion in the tire raises the pressure x times (10 times in this case) faster. I.E. With a non-loaded tire running 20psi conforming over a rock reducing the volume by 5% only causes a 5% increase in pressure, but if the volume (air, liquid doesn't compress) was reduced by 10 times that now would be a 50% increase in pressure. Translated = It'll ride harder over obstacles and bumps.