calibear2003 4 #1 Posted January 18, 2014 Hello, I was just wondering if the 1100 eaton hydro's were heavier then the 1 1/8 8 speeds? It just seems that whenever I need to slide one over via the back end, my 314-8 seems to sort of move, but the 312-H is just glued to the floor. The hudro just seems to be noticeably heavier. I can not find any spec's to answer my question.... Thanks..... Share this post Link to post Share on other sites
boovuc 1,090 #2 Posted January 18, 2014 (edited) The Eaton hydro rear is heavier than the UniDrive rear. The exact weight and or a ballpark by how much I don't know. I just know by experience that the hydros are heavier. Especially the older Sundstrand rears. There is about a 50 lb weight difference between the 520 8 speed and the 520-H. (600 lbs dry weight for the 8 speed verses 650 lbs for the 520-H). Edited January 18, 2014 by boovuc Share this post Link to post Share on other sites
squonk 41,414 #3 Posted January 18, 2014 Try dragging a 520 transaxle from the show grounds. Then you will know how heavy they are! Thanks again Jay! Share this post Link to post Share on other sites
leeave96 487 #4 Posted January 19, 2014 I would haved guessed the hydro would be lighter than the 8 speed. When I look at my 520H and 314-8 from the rear, the 8 speed looks beeffier/wider and I should think the 8 speed has more gearing - just because it is an 8 speed. More gears to me seems like more metal and a bigger housing to hold it and therefore more weight. I've never tore into a hydro, but I'm thinking one speed gearing vs 8 inside. So why is the hydro tranny heavier? I'm thinking its the pump, i.e. the Eaton 11 or the Sunstrand. Now one might say the pump is an integral part of the hydro, but in some ways its really a power input device, just like the belt pulley is the input device with a gear drive. So if you separate the tranny input device, pulley or pump, maybe the 8 speed tranny is heavier than the hydro tranny. That and 50 cents might get you a cup of coffee... Bill Share this post Link to post Share on other sites
bmsgaffer 2,045 #5 Posted January 20, 2014 (edited) The 8 speed, even though it has 8 speeds is a hollow cast housing with some heavy gears running around inside it. A hydro has the hydraulic pump AND a hydraulic motor each of which you could essentially equate to a solid chunk of steel with all internal parts (Like an engine block, mostly solid with pistons or balls running around inside making the fluid move). Then you have to add the cast diff housing and a few gears. Plus you have all the hydraulic equipment like the lift cylinder, valves for controlling lift and speed, charge pumps, flow valves etc.... But that stuff is all external to the transaxle itself. Edit: Checked the manual, difference in C-165 8 speed vs hydro is 40lbs total. Not as much as I would expect, but still enough to notice since most of it is probably squarely on the back tires.. Edit 2: Also just to note, on these models the pump and motor are one physical unit. The way I worded it made it sound like they were separate. Edited January 20, 2014 by bmsgaffer Share this post Link to post Share on other sites
