How to ID 3:73 gears
- Thread starter ukaviator
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Marks seems to have 3.73 listed for the 80 series now... am I missing something, or maybe this is a new offering.
http://www.marks4wd.com/drive-line/diff-gears/toyota/dgland80.html
http://www.marks4wd.com/drive-line/diff-gears/toyota/dgland80.html
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I haven't read the whole thread, but I can supply 3.73 gears for the 80 series as well. Prices are reasonable, but availability may be low - need to enquire.
Shipping will be the big question as the weight is fairly high on these.
John
Shipping will be the big question as the weight is fairly high on these.
John
John, do you have complete diff assemblies or gears only? They are available and Akella has helped us with a page or two ago with the Toyota part numbers. I was inquiring as to if anyone has installed them and what the impressions are in regard to RPM reduction in 5th gear and whether the time ($$$) and trouble are worth it.
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I can supply just the ring and pinion gear sets (and installation parts too, just not complete diffs).
I've been looking in to this over the past few years as my HZJ77 felt very under-geared with the 4.11s and the H55F - and it comes with the 9.5" rear and the high pinion 8" in the front - pretty much the same as the 80 series.
My own HJ61 has the factory 3.70s in it, and being able to drive both my HZJ77 and my HJ61 back to back (same tires, same lift, same transmission etc.) - the HJ61 was by far the better drive on the highway with lower RPMs, better fuel economy, and better top speed.
With 255 85R16s the HJ61 revs about 2450 rpm at 120 Km/hr, and the HZJ77 (which I have since, regrettably, sold) would rev more like 2700 rpm - which was just too much.
So, yes, big difference for me with that comparable.
Now, I have a 5 speed HDJ81 here (that was in a wreck) and the previous owner was quite interested in finding 3.73 gear sets for it, but the ones I located at the time were going to be too costly. I now have a new supplier and the gear sets are reasonably priced but they would likely have to be sea freight shipped or included with a fairly large order to keep shipping costs in line.
I was thinking of converting a US spec FZJ80 to a 1HD-T and 5 speed that I have sitting here and I would certainly go with the 3.73 diff gears if I did that.... however, I have to be realistic about the life of a small business owner - I won't likely have the time to do the conversion so I've put the engine, trans and other parts from the (still running) donor up for sale in the classifieds.
I'll send off an enquiry shortly to find out how many gear sets are available in the 3.73 ratio.
Now, having said all that, I have seen even more ratios available: 3.727, 3.909, 4.30, and somewhere I recall seeing something in the 3.5 range.
~John
I've been looking in to this over the past few years as my HZJ77 felt very under-geared with the 4.11s and the H55F - and it comes with the 9.5" rear and the high pinion 8" in the front - pretty much the same as the 80 series.
My own HJ61 has the factory 3.70s in it, and being able to drive both my HZJ77 and my HJ61 back to back (same tires, same lift, same transmission etc.) - the HJ61 was by far the better drive on the highway with lower RPMs, better fuel economy, and better top speed.
With 255 85R16s the HJ61 revs about 2450 rpm at 120 Km/hr, and the HZJ77 (which I have since, regrettably, sold) would rev more like 2700 rpm - which was just too much.
So, yes, big difference for me with that comparable.
Now, I have a 5 speed HDJ81 here (that was in a wreck) and the previous owner was quite interested in finding 3.73 gear sets for it, but the ones I located at the time were going to be too costly. I now have a new supplier and the gear sets are reasonably priced but they would likely have to be sea freight shipped or included with a fairly large order to keep shipping costs in line.
I was thinking of converting a US spec FZJ80 to a 1HD-T and 5 speed that I have sitting here and I would certainly go with the 3.73 diff gears if I did that.... however, I have to be realistic about the life of a small business owner - I won't likely have the time to do the conversion so I've put the engine, trans and other parts from the (still running) donor up for sale in the classifieds.
I'll send off an enquiry shortly to find out how many gear sets are available in the 3.73 ratio.
Now, having said all that, I have seen even more ratios available: 3.727, 3.909, 4.30, and somewhere I recall seeing something in the 3.5 range.
~John
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Ok, I have 80 series 3.73 gear sets available. Limited quantities at this point, but I can get more.
Best shipped by sea freight from my wholesaler as they are heavy, but I can ship with my other larger orders as well for fairly decent rates... I will try to figure out selling prices taking in to account the shipping weight.
...more to follow...
~John
Best shipped by sea freight from my wholesaler as they are heavy, but I can ship with my other larger orders as well for fairly decent rates... I will try to figure out selling prices taking in to account the shipping weight.
...more to follow...
~John
John, in reference to your post about the trucks with same tires, transmission and lift but different diff center ratios etc., did your fuel mileage improve or not? If so how much? Noticeable or not so much?
What's your usual driving terrain, city? Highway? Mixed? Average speeds on average trips? How about hilly terrain or similar? I guess my question relates to an overall driving experience/application in relation to overall impression(s).
Will the gear sets you make available to us be Genuine Toyota or aftermarket?
Did you notice a difference between the two trucks power/acceleration-wise overall or not so much?
My next question (will vary between participants/readers), but given the amount of work and money involved in a diff gear swap would you recommend doing this if it were your truck? Specifically an 80 series turbo diesel with an H15* transmission.
I do respect your opinion and input. I do understand it is your $.02 and experiences and recommendations related to said so I value that for certain.
Thanks very much in advance and look forward to hearing what you have to say here.
What's your usual driving terrain, city? Highway? Mixed? Average speeds on average trips? How about hilly terrain or similar? I guess my question relates to an overall driving experience/application in relation to overall impression(s).
Will the gear sets you make available to us be Genuine Toyota or aftermarket?
Did you notice a difference between the two trucks power/acceleration-wise overall or not so much?
My next question (will vary between participants/readers), but given the amount of work and money involved in a diff gear swap would you recommend doing this if it were your truck? Specifically an 80 series turbo diesel with an H15* transmission.
I do respect your opinion and input. I do understand it is your $.02 and experiences and recommendations related to said so I value that for certain.
Thanks very much in advance and look forward to hearing what you have to say here.
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Workhorse - good questions, and I'll try to provide sensible and useful answers.
Driving is a mix of town, highway, off-road. I also have a reasonable comparison of also doing a very similar trip for two different winters down to Death Valley and back with almost an identical load on the vehicles. RTT, ARB bumper with winch, same tires etc. I also have long term data from my HJ61 and about 15,000Kms of data from my HZJ77 - the HJ61 wins out every time, and by quite a lot.
The main - and very important variable - is that the HZJ77 has an indirect 4.2L 1HZ with Denco aftermarket turbo, and the HJ61 has the 4.0L 12H-T with direct injection and stock turbo turned up to 12PSI. A direct injected engine is by its very nature more efficient than an indirect injection engine, however the power output - judging by seat-of-the-pants feel (and going up and down local hills on a regular basis) - is very similar.
The HJ61, driven considerably faster - 120-130 kph, compared to the HZJ77 driven at about 100-110 (as an example of typical long term cruising speeds) obtained far better fuel economy right across the board. I'll have to go back and dig up the numbers, but it was quite substantial. However, I'm not exactly comparing apples to apples here, the engines are quite different in brake specific fuel consumption.
The gears: front set is OEM, rear set is Japanese made aftermarket.
Acceleration: the HZJ77 was much slower off the line (due to the lower gearing and much greater bottom end power of the 1HZ-T) than the HHJ61, but once up to speed they were very similar. The 12H-T is a 'snappier' engine and is very throttle sensitive, the 1HZ is not as quick to rev, but has a greater rev range and higher redline.
If it was my truck? Yes, absolutely! And it's one of the reasons why it was one of the first things I asked my new supplier about. I would like to replace my HJ61 with another HZJ77 and I would have to have taller gears (and a 1HD-T). I have a BJ74 with cable lockers, and I was almost going to rob the front out of that to replace the front end in the 77 and put 3.70s in it.
The only downside is losing some low speed crawl, but that can be offset with transfer case gears in both the 70 and 80 series.
hth, John
Driving is a mix of town, highway, off-road. I also have a reasonable comparison of also doing a very similar trip for two different winters down to Death Valley and back with almost an identical load on the vehicles. RTT, ARB bumper with winch, same tires etc. I also have long term data from my HJ61 and about 15,000Kms of data from my HZJ77 - the HJ61 wins out every time, and by quite a lot.
The main - and very important variable - is that the HZJ77 has an indirect 4.2L 1HZ with Denco aftermarket turbo, and the HJ61 has the 4.0L 12H-T with direct injection and stock turbo turned up to 12PSI. A direct injected engine is by its very nature more efficient than an indirect injection engine, however the power output - judging by seat-of-the-pants feel (and going up and down local hills on a regular basis) - is very similar.
The HJ61, driven considerably faster - 120-130 kph, compared to the HZJ77 driven at about 100-110 (as an example of typical long term cruising speeds) obtained far better fuel economy right across the board. I'll have to go back and dig up the numbers, but it was quite substantial. However, I'm not exactly comparing apples to apples here, the engines are quite different in brake specific fuel consumption.
The gears: front set is OEM, rear set is Japanese made aftermarket.
Acceleration: the HZJ77 was much slower off the line (due to the lower gearing and much greater bottom end power of the 1HZ-T) than the HHJ61, but once up to speed they were very similar. The 12H-T is a 'snappier' engine and is very throttle sensitive, the 1HZ is not as quick to rev, but has a greater rev range and higher redline.
If it was my truck? Yes, absolutely! And it's one of the reasons why it was one of the first things I asked my new supplier about. I would like to replace my HJ61 with another HZJ77 and I would have to have taller gears (and a 1HD-T). I have a BJ74 with cable lockers, and I was almost going to rob the front out of that to replace the front end in the 77 and put 3.70s in it.
The only downside is losing some low speed crawl, but that can be offset with transfer case gears in both the 70 and 80 series.
hth, John
I may be interested in some 3.73's for my 80 series in the future. I want to see how it is with a manual transmission first.
Yeah it's going to be a NV4500 so I have a more practical OD. I may still want to lower the cruise Rpm a bit more tho.
I talked to a guy in the UK who sold me my H151F and he runs 35s with 3.73s and H151 and he says he loves it. I could imagine it would struggle, however his highway RPMs are around 1800 - 2000 at 100 km/h. 3.73s are standard in Europe I believe since they need eco - gears for fuel cost reasons I'm sure...
I run 2450 RPM at 100 km/h with 33s and 4.11s. Makes for long road trips but LOVE the extended fuel economy around town.
Food for thought.
John any update on this?
It's looking like the 6bt going into my 80 will be turning 2200rpm at my normal cruse speed. Well out of its efficiency area. Going to 3.73's will help this quite a bit I think.
Would like to know this as well.
I could probably get full 3.73 diffs from where I got my H151 from the UK...
I could probably get full 3.73 diffs from where I got my H151 from the UK...