bill65 Posted November 22, 2012 Share Posted November 22, 2012 I have an 84 Sunrader with 22r and 4speed that is geared high in 1st gear.Does anyone have experience with lowering 1st.gear ratio? Quote Link to comment Share on other sites More sharing options...
Derek up North Posted November 22, 2012 Share Posted November 22, 2012 I don't remember anyone posting here about playing with the internal ratios. Some have changed the diff from the (probable) 4.10:1 to either 4.56:1 or 4.88:1. Quote Link to comment Share on other sites More sharing options...
zero Posted November 22, 2012 Share Posted November 22, 2012 I have an 84 Sunrader with 22r and 4speed that is geared high in 1st gear.Does anyone have experience with lowering 1st.gear ratio? Seems the easiest way to do it is to install a newer 5 speed with the lower 1st gear and higher 5th gear. You then have new advantages on both ends. Low 1st gear and lower RPMs in high gear IF you have a use for it. All depends on what trans you have now. If you have a trans with a 3.2 ratio first gear, there are other 4 speeds with a 3.5 ratio first gear. If you already have a 3.5 ratio in first, there are two five speeds used in Toyota trucks that have a 3.9 ratio first gear. A good transmission can usually be found for $300 or less and they can be shipped by UPS which makes things easy. I just bought one from 1200 miles away and it cost $75 to ship it to me. Seems swapping the trans is by far the easiest route. Changing the rear axle ratio is more work and more expensive and then you lose top end. W40 four speed First Gear: 3.287:1 W42 four speed, 1980s . First Gear: 3.579:1 W45 four speed, 1980s. First Gear: 3.566:1 W50 five speed, 1976-1982. First Gear: 3.287:1 W55 five speed, 1984-88. First Gear: 3.566:1 W56 five speed, 1985-1995. First Gear: 3.954:1 W59 five speed. First Gear: 3.954:1 Quote Link to comment Share on other sites More sharing options...
Derek up North Posted November 23, 2012 Share Posted November 23, 2012 Toyota motorhomes don't have 'Top end'! Quote Link to comment Share on other sites More sharing options...
zero Posted November 23, 2012 Share Posted November 23, 2012 Toyota motorhomes don't have 'Top end'! Going down a hill does (sometimes). Probably the ideal combo is a 4.88 axle ratio and a W56 trans with .8 overdrive. But that is a lot of messing around. Here's what some changes would be for various types of changes: With no over-drive in high gear at 65 MPH: 4.10 – 25.5” tires – no OD – 3500 RPM at 65 MPH 4.37 - 25.5” tires – no OD – 3850 RPM at 65 MPH 4.88- 25.5” tires – no OD – 4300 RPM at 65 MPH 5.29- 25.5” tires – no OD – 4650 RPM at 65 MPH 5.62 - 25.5” tires – no OD – 4950 RPM at 65 MPH With a five-speed and over-drive in high at 65 MPH: 4.10 – 25.5” tires – with .8 OD – 2750 RPM at 65 MPH 4.37 - 25.5” tires – with .8 OD – 2950 RPM at 65 MPH 4.88- 25.5” tires – with .8 OD – 3300 RPM at 65 MPH 5.29- 25.5” tires – with .8 OD – 3600 RPM at 65 MPH 5.62 - 25.5” tires – with .8 OD – 3850 RPM at 65 MPH Transmission, stock 4.10 ratio axle and in 1st gear at 1200 RPM: W40 four speed First Gear: 3.287:1 - 12 MPH W42 four speed, 1980s . First Gear: 3.579:1 – 11.5 MPH W45 four speed, 1980s. First Gear: 3.566:1 – 11.5 MPH W50 five speed, 1976-1982. First Gear: 3.287:1 – 12 MPH W55 five speed, 1984-88. First Gear: 3.566:1 – 11.5 MPH W56 five speed, 1985-1995. First Gear: 3.954:1 – 11 MPH W59 five speed. First Gear: 3.954:1 – 11 MPH A 4.88 rear and W56 five-speed would give; 1st gear at 1200 RPM - 10 MPH 5th gear OD @ 65 MPH – 3300 RPM Quote Link to comment Share on other sites More sharing options...
5Toyota Posted November 23, 2012 Share Posted November 23, 2012 as for the amount of work changing trans vers changing the diff its about a toss up to me have done both on toyota but not on a toyhouse Quote Link to comment Share on other sites More sharing options...
Maineah Posted November 23, 2012 Share Posted November 23, 2012 How much do you want to spend? Is it worth it? Quote Link to comment Share on other sites More sharing options...
zero Posted November 23, 2012 Share Posted November 23, 2012 as for the amount of work changing trans vers changing the diff its about a toss up to me have done both on toyota but not on a toyhouse Just about anybody that can turn a wrench can swap a transmission. Changing a set of gears in a rear axle is much more complex and takes expertise. Changing the entire center-section with a complete used one not so complicated. To change a ring and pinion there is a lot of set-up. Pinion depth, bearing preload, backlash, etc. Not an easy job even for many some mechanics and I've seen a few get ruin at repair shops. Quote Link to comment Share on other sites More sharing options...
Derek up North Posted November 23, 2012 Share Posted November 23, 2012 Agreed setting up a new ring & pinion is a PITA. That's why everyone I've ever heard of on here just swaps in a complete center section. Quote Link to comment Share on other sites More sharing options...
zero Posted November 23, 2012 Share Posted November 23, 2012 Agreed setting up a new ring & pinion is a PITA. That's why everyone I've ever heard of on here just swaps in a complete center section. Yes, but when it comes to the Toyota full-floating rear . . . if a person already has a 4.10 and wants to go higher- chances of finding a complete center-section are probably near zero. Aftermarket ring and pinion sets are available and likely the only choice. Too bad since Toyota uses a removeable carrier very similar to Ford - unlike the many GM axles that are Salisbury (no carrier that comes out as an assembly). Quote Link to comment Share on other sites More sharing options...
WME Posted November 23, 2012 Share Posted November 23, 2012 There are 5 used stock 4.88 center sections on Ebay and 8 rebuilt ones with limited slips added. . Quote Link to comment Share on other sites More sharing options...
zero Posted November 23, 2012 Share Posted November 23, 2012 There are 5 used stock 4.88 center sections on Ebay and 8 rebuilt ones with limited slips added. . Do you know, for sure, that those center sections from non-floating rears on Ebay fit the full floaters? They look the same at a glance but can't say I ever tried to swap one in. Quote Link to comment Share on other sites More sharing options...
Derek up North Posted November 23, 2012 Share Posted November 23, 2012 AFAIK, ALL Toyota 8" centers interchange. Doesn't have to be from a FF. (The axle codes on the doorpost only refer to the ratio, not whether it's FF or Semi.) eg G284. Quote Link to comment Share on other sites More sharing options...
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