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| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 319 Registered: 3-2007 Posted From: 71.55.193.233 Rating: N/A |
I have a friend that installed a v-730 allison tranny and now needs to change the rear end to achieve faster speed. It has a 4;10 ratio. what is recommended for it and where can one be located? Right now top end is around 53-55 mph | ||||||||||||||||||||||||||
| Pete/RTS Daytona (Pete_rtsdaytona)
Registered Member Username: Pete_rtsdaytona Post Number: 503 Registered: 1-2005 Posted From: 97.104.4.244 Rating: N/A |
Somethings WRONG HERE My first guess is he needs to shift out of SECOND GEAR !!!! a 4.10 rear with a v730 with it's (.88 to one third gear) should go 74 to 77 miles per hour at 2150 RPMs I know - cause that's what I have in my RTS | ||||||||||||||||||||||||||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 320 Registered: 3-2007 Posted From: 71.55.193.233 Rating: N/A |
I'll check it out Pete and see what is going on. I heard that most of the times the rear needed to be changed and I never thought that it wasn't shifting. I'll let him know. Thanks gomer | ||||||||||||||||||||||||||
| Jim & Linda Callaghan (Jimc)
Registered Member Username: Jimc Post Number: 57 Registered: 2-2004 Posted From: 66.175.206.159 Rating: N/A |
I agree with Pete, my 4106 will run 70-75 all day long with a 4.10 rear, although I prefer 65-68 it just seems ti like it there. Those speeds are from both the electric speedo, and a GPS so I know they are correct. Jim | ||||||||||||||||||||||||||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 521 Registered: 10-2006 Posted From: 66.90.229.163 Rating: N/A |
The 4.10 ratio is it , there are NO faster rear gears made .Although there may have been a 2 speed rear at bone time. To go faster a different tranny the VS 2-8 might help, but the hill climbing of this unit with the high final ratio , means a downshift for any grade bigger than a speed bump. If he is in a real hurry tweaking the gov to 2400rpm , "fire truck" setting may be OK but engine life will suffer as will fuel mielage. 1950 rpm is about the top of the good fuel mileage . FF | ||||||||||||||||||||||||||
| Tom Christman (Tchristman)
Registered Member Username: Tchristman Post Number: 34 Registered: 1-2006 Posted From: 66.218.33.156 Rating: N/A |
With 4.10 rear end ratio and the .88 top gear of the V730 this is the top speed with various tires at 2100rpm- 11R-22.5- 70mph. 12R22.5- 72mph. 11R24.5- 73mph. I have 4.56 with 11R24.5 and the V730. My 2100rpm cruise is 65.6mph and with my engine turned up to 2400rpm, I can get 75mph out of it. Good Luck, TomC | ||||||||||||||||||||||||||
| E. R. Red Ruby (Beatsworkin)
Registered Member Username: Beatsworkin Post Number: 19 Registered: 2-2006 Posted From: 76.253.186.190 Rating: N/A |
Gomer Does your friend have have air throttle on his bus ? If so please respond as I could have clue for you. Red | ||||||||||||||||||||||||||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 321 Registered: 3-2007 Posted From: 71.55.193.233 Rating: N/A |
I talked to him today and told him about the tranny not changing and he was on the road and will check it out. I told him that I thought that they only had one gear ratio in the rear and I felt it was the tranny so we will go from there. It has manuel throttle I know.Thanks again. Gomer | ||||||||||||||||||||||||||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 860 Registered: 12-2000 Posted From: 70.0.172.154 Rating: N/A |
Can he confirm engine RPM vs speed? That will tell everyone right away what is going on. Jack | ||||||||||||||||||||||||||
| E. R. Red Ruby (Beatsworkin)
Registered Member Username: Beatsworkin Post Number: 20 Registered: 2-2006 Posted From: 76.253.186.190 Rating: N/A |
Gomer Have your friend call me most any time on my cell 309-224-8998 I had same problem maybee I can help Red | ||||||||||||||||||||||||||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 1382 Registered: 12-2000 Posted From: 76.66.17.110 Rating: N/A |
Hey Red! Share with the rest of us too! Another thing from my thoughts: The V730 won't shift into 3rd gear if the tranny fluid is low. It'll run all day in 2nd, just won't shift. Yes, transit knows how to abuse the equipment... Something else to check? happy coaching! buswarrior | ||||||||||||||||||||||||||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 523 Registered: 10-2006 Posted From: 66.90.229.76 Rating: N/A |
".88 top gear of the V730" Don't have my book here but I seem to remember .88 as the 4 speed number , not the 730 number. That's why a slush pump swop usually costs 6-8mph + at cruise. | ||||||||||||||||||||||||||
| Pete/RTS Daytona (Pete_rtsdaytona)
Registered Member Username: Pete_rtsdaytona Post Number: 504 Registered: 1-2005 Posted From: 97.104.13.202 Rating: N/A |
You must be getting old f/f - I guess you don't have much of a memory left It's .88 (just like I said) see--> http://www.industrialautomatic.com/html/vspecs.htm we've been down this same path before - ooops bet you don't remember that either Pete RTS/Daytona (Message edited by pete rts/daytona on November 07, 2008) | ||||||||||||||||||||||||||
| Frank Allen (Frank66)
Registered Member Username: Frank66 Post Number: 95 Registered: 10-2005 Posted From: 205.188.117.73 Rating: N/A |
i have a 410 rear end in my 06, it runs 77 mph, even when i had the slower rear end it still ran about 67, if top end speed is only 55nor so either you have the wrong rear end (not 410) or the transmision is not going to high gear or the engine rpm is way down, will be one of those things the 410 is the fastest rear end avail for the 06 Frank Allen 4106 | ||||||||||||||||||||||||||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 525 Registered: 10-2006 Posted From: 66.90.229.178 Rating: N/A |
Indeed the slushpump does list a .880 Od , but my book shows the stick at .808. So the slushpump would act as if as a straight thru it had a 3.608 rear end and the stick would have a 3.3128 Only a small difference number on paper but fairly good speed loss if you plug both thru Daris computer . Unless you love cruising at 2400rpm, Do it your way , FF | ||||||||||||||||||||||||||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 322 Registered: 3-2007 Posted From: 71.55.193.233 Rating: N/A |
update:: I found that the tranny was pulled out from a bus that used air throttle and he is going to call red ruby for more info on that part. He doesn't know the rpms yet and will look into that along with fluid level of the tranny. I will keep you informed as I get the info. I told him what was posted here and he said majority rules. GO BUSNUTS. Next election, call us first,as we are da main men, and women LOL Gomer | ||||||||||||||||||||||||||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 612 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
Gomer, It sure sounds like the throttle lever on the trans is in the full throttle position, regardless of the actual throttle position. Changing from a stick to an auto requires a piece of linkage between the engine governor and the trans, or a second air cylinder on the trans, if using an air throttle. A quick and easy way to find out what's happening, is to ask him how many "shifts" he feels. The answer should be three, one shift, the converter lockup, and another shift. If only two, he's only getting to 2nd gear lockup. Next thought is that the throttle linkage was disturbed during the swap, and even though the pedal goes to the floor, the linkage may not be moving the governor lever all the way to the full speed position. Its not the rear end ratio. Remember also, that power requires fuel. When were the fuel filters changed last, and could there be a small suction leak? Happy hunting, George | ||||||||||||||||||||||||||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1442 Registered: 12-2000 Posted From: 67.181.166.160 Rating: N/A |
George - The V-730 feels like a four-speed as it upshifts: one, lockup, two, three. Similar to how the HT-740 feels like a five-speed: one, lockup, two, three, four. Sounds like the air throttle modulator on the side of the V-730 isn't hooked up. There should also be a "T" in the air throttle line to operate the modulator. Pete & Fred - The literature I have shows the V-730 as having a bevel gear ratio of 0.875:1, and the manual Spicer for the 4106 and later as 0.808. 4104s and earlier used a 1:1 bevel set. GM's specs were set up using tires that turned 495 revs per mile, equaling 60 mph at 1650 rpm for the 4106. I found a Bridgestone 11R22.5 drive axle tire that turns 496 rpm, almost identical to GM's original. Plugging that into Daris's calculator yields the following road speeds at three different tach readings:
Now, I found another Bridgestone model drive tire in 11R24.5 that turns 470 revs per mile. Plugging that tire into Dari's calculator yields the following:
I guess the point I'm trying to make here is that with the limited rear axle ratios available to GM owners, by careful tire selection after converting to an automatic, you can obtain near-stock road speeds. Fuel mileage will still suffer slightly, especially if you do a lot of city driving, but highway mileage would improve somewhat - and every little bit helps, eh? FWIW & HTH. . .  | ||||||||||||||||||||||||||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 613 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
RJ, I don't want to be picky, but I think thats what I said? What will be felt is 1-2, lockup, then 2-3. You and I both agree that the modulating lever on the trans is probably in the full throttle position. Gomer mentions a mechanical throttle, so there probably wasn't a modulating cable installed. But, the trans should upshift at near max rpm even if the mod is in the full speed position. If the air mod cyl is still there, with no air, it should indicate closed throttle? So, maybe the throttle linkage isn't adjusted properly either. We just gotta hear more... Regards, George | ||||||||||||||||||||||||||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 327 Registered: 3-2007 Posted From: 71.55.193.233 Rating: N/A |
ok,guys. The coach 4106 has no air throttle on the engine. It is of course, an 8v-71. It was a 4-speed and after swapping for the 730 it isn't shifting into 3rd gear. What do da man need to resolve the situation? we checked it all out and this is what we found. It is turning a little slow on the rpm,s around 1800 and he is going to turn er up and fix that. Thanks in advance. Gomer | ||||||||||||||||||||||||||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 614 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
Gomer, As BW said, the trans won't shift into 3rd if it is low on fluid, so that is the first and easiest thing to check. While hot, idling in neutral. Secondly, the governor must be set for about 2150 no load rpm, and the throttle linkage MUST move the governor speed lever to the full speed position when the pedal is fully depressed. Thirdly, an automatic transmission must be modulated. What? The trans has to know where your foot is so it knows when to shift, so linkage (or a cable) must be connected between the trans and the governor speed lever. (In the former air throttle application, two air cylinders were used, one on the engine, one on the trans.) IF the trans was installed without modulation, which a bunch of us think happened, and the trans lever was left in the full throttle position when installed, it probably wouldn't upshift at 1800 RPM? Another thought, if the trans has the proper linkage, resetting the gov may clear the problem, because right now the trans is seeing full throttle, and the engine won't go above 1800, so the trans doesn't think it should upshift? I hope the shift linkage is properly installed??? Now we really want to know what you find! Happy hunting, George | ||||||||||||||||||||||||||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 615 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
Another question, which I should have thought of sooner... 53-55MPH at 1800RPM in 2nd gear? Using the speed calculator posted above, the top speed in 3rd gear would only be about 60-61mph at 1800RPM? Were we quoted a no-load 1800RPM, or a dash mounted tach reading 1800RPM in gear under load? Pete was really right way up there, "Somethings WRONG HERE!" It sounds like his tach, and/or his speedo may be off as well. (Couldn't be because he just changed the trans could it?) {I don't know where his speedo is driven from, trans or left front brake drum.} Now Gomer's really got homework to do! George | ||||||||||||||||||||||||||
| James Stacy (Jimstacy)
Registered Member Username: Jimstacy Post Number: 150 Registered: 1-2001 Posted From: 99.153.149.196 Rating: N/A |
Hey guys, is he sure he has a highway V730? They had an overdrive final but the model used on some transits had an underdrive! I don't know if it is changeable or if the tranny needs to be changed. IIRC the system for "no shift to third" was a jet of oil aimed at a plate that prevented the upshift if hit by the jet. This was at about 3 quarts low. If the fluid was up it blocked the jet from striking the plate and allowed the upshift. That system could be malfunctioning. BTW it is normal to have a convertor locked up SOMETIMES while in first gear. When downshifting from second the converter is still locked (very obvious with Jake Brake working). Converter then unlocks before stopping. I was never sure if the first "upshift" was the lock up or the 1 to 2 shift as everyone assumes. I better get out "da book. Jim Stacy | ||||||||||||||||||||||||||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 335 Registered: 3-2007 Posted From: 71.55.230.210 Rating: N/A |
Well I found out that it is a "V-730-B6, 23012778 is the other number on the data plate. Now did they make a city gear and highway gear? If it is a city gear can it be changed to highway without a lot of $$$$. That is all I have at this time, and thanks for the info up to this point. Gomer | ||||||||||||||||||||||||||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 1225 Registered: 10-2003 Posted From: 71.58.110.9 Rating: N/A |
Went through this a couple of years ago. There is only one ratio of internal angle gears for the V-730's. They are listed as a matched set by two part numbers. One is for non pto and the other number is for pto equipped units. This theory probably came about from the two ratios available for the VS series. | ||||||||||||||||||||||||||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 634 Registered: 8-2006 Posted From: 76.91.197.153 Rating: N/A |
Gomer where are you? Inquiring minds want to know. G | ||||||||||||||||||||||||||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 352 Registered: 3-2007 Posted From: 71.55.230.210 Rating: N/A |
George; It still won't change even with the r's at 2200 rpm. Can't figure out what is going on and still no answers to output ratios, city or highway. There ain't no resonable reason for it to do what it ain't doing LOL I am and He, still looking for answers. Gomer |