3B, 5 speed, 3.73 gears, 33" tires... ? (1 Viewer)

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amaurer

amaurer

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Moose needs new shoes - how will my BJ73 (no turbo) handle 33's? H55, stock 3.73 gears.

I understand it'll be slower off the line. What about highway speeds, still acceptable?

And the kicker - my daily commute has 2000' of elevation change. Right now I take the worst sections of it at 60kph to keep the EGTs down. Will I be able to keep that up, at least?
 
I have a bj60 with a non turbo 3b with 33x10.5 with 3.73s. Its slow. some of the mountain passes were taken in 3rd barely. But those were 7-8k feet. now I put a touring rack 100lbs bull bar 100 lbs warn winch 100 lbs rtt 100 lbs and my M416 trailer about 1000lbs loaded.

Needless to say one camping trip through those mountians this year and I just finished ordering my turbo kit from diesel42 this evening. I don't even have it yet and I will tell you it was the best 2200 I have ever spent.
 
if you were driving on level ground the hiway speeds would be acceptable...was for me anyways. good gas mileage too its just getting it to hiway speeds and keeping it there when you have a 2000' vertical commute. that will be the hard part.
 
It wil make you down shift more often when climbing, take alot longer to get up to speed as in hwy speed, increase your egt's and probably won't help fuel consumption.
Install 4.10 or 4.11 gears and never look back.

Jim
 
I've been doing it every day for, um, 8 months? Doesn't bother me at present, but I don't want to make it TOOO much worse. Truck is presently on 31's.

Its basically a single 10 mile pull from sea level to 2000'. I can do most of it at 80-90kph in 4th but have to drop to 3rd for the final 1/2 mile at 60kph. This is to avoid my self-imposed EGT limit of 1250F.
 
It's gonna make it worse... 33's would be similar to a gear change of 3.30 or there abouts. You may want to consider a gear change if you go to 33's. I am running 33's with 4.88's in my 60 and she is slow but I am still not going to put a turbo on this thing.

Tony
 
My BJ60 has 235/85/16 's which come out right close to 31" in diameter. The rear diff ratio is 3.70. There is an AXT turbo assisting the engine breathing as well as 2.5 inch straight exhaust. But even with the additional aid of the boost this engine is at it's limit to pull its load along at highway speeds if there is a headwind or hills. To make yourself happy with 33's you wlll need a gear change or a modern engine with an earlier torque rise.
 
Doug384 said:
My BJ60 has 235/85/16 's which come out right close to 31" in diameter. The rear diff ratio is 3.70. There is an AXT turbo assisting the engine breathing as well as 2.5 inch straight exhaust. But even with the additional aid of the boost this engine is at it's limit to pull its load along at highway speeds if there is a headwind or hills. To make yourself happy with 33's you wlll need a gear change or a modern engine with an earlier torque rise.
Click to expand...

Really? Something must be up with your turbo/fuel settings...I have 265/75/16 (32") with stock 3.7 gearing and have no problems in a headwind or moderate hills keeping up highway speeds with my turbo'd BJ60....I honestly like the 3.7 gears as it will keep the RPM's lower upon cruising at highway speeds....
 
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I think the consensus here is you should be alright. Worst case scenario is you may want to gear down. Whether that means 4th-3rd, 3rd-2nd, or 3.73-4.11s.
One's cheaper but requires a bit of patience. If you are going to be doing these hills indefinitely, I would spend the 180bux on a pyro just so you can keep an eye on your EGTs. This way you will know if you are pushing your truck too hard or not.
 
Really? Something must be up with your turbo/fuel settings...I have 265/75/16 (32") with stock 3.73 gearing and have no problems in a headwind or moderate hills keeping up highway speeds with my turbo'd BJ60....I honestly like the 3.73 gears as it will keep the RPM's lower upon cruising at highway speeds....

Be realistic here! When the throttle is called upon at cruising speed in top gear it is slow to respond. Boost is low and fuel is moderate so EGT's are mild to say the least. What is the point in trying to make this little ancient engine do things it won't like? I'll just poke along. The flow can pass when they get the chance. The latest round of trucks with diesels are like the old high performance gassers of yesteryear. There is no comparison and no way to keep up either!
 
Yep, 33 w/3.73 is correct ... but it is at the limit of acceptability.

I had a BJ60 w/32" and I have a BJ70 w/265/75R16 and it conformatble but, as has been said, the hills is long to climb ... especially on the long highway hills where it's almost... embarrassing. :eek:
 
I know that the AXT turbos drive VERY differently than the D42 kit. I was playing around with my throttle pull yesterday at a stop light and was able to see 1-2 psi with just a little above idle. That was without even being in gear so no load at all!

I would say, if you come to decide to regear, put that money into a turbo for the truck and never look back. I am going to start playing with my setup as I have 33's, 4.11s and an H41 on a BJ44 so similar wheelbase to yours. I am going to swap an H55 in next weekend and see how that goes. I also have a set of 35s I will swap on. If I still don't like the way it drives (DD), I will regear to 3.73. It's nice I can play around with each step and see how I like it. I'll let you know how it goes...
 
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Doug384 said:
Really? Something must be up with your turbo/fuel settings...I have 265/75/16 (32") with stock 3.73 gearing and have no problems in a headwind or moderate hills keeping up highway speeds with my turbo'd BJ60....I honestly like the 3.73 gears as it will keep the RPM's lower upon cruising at highway speeds....

Be realistic here! When the throttle is called upon at cruising speed in top gear it is slow to respond. Boost is low and fuel is moderate so EGT's are mild to say the least. What is the point in trying to make this little ancient engine do things it won't like? I'll just poke along. The flow can pass when they get the chance. The latest round of trucks with diesels are like the old high performance gassers of yesteryear. There is no comparison and no way to keep up either!
Click to expand...

I'm realistic, honestly. You're right, we can't keep up with 300+HP V8 diesel belching Dodge's but then that's not why we drive Landcruisers. BUT they can be made to perform considerably better than they did when they rolled off the assembly line. To each their own. I like mine running the way it is, I can take moderate hills in 5th and hold 110km/hr no problem, when I want to pass someone on the flat who is doing 100km/hr, I get instant boost and is not slow at all to respond, and I can pass quite easily.... this is my reality and I'm happy about it ;) Mind you, I sourced my own turbo and believe it's a much better fit for our truck than the AXT....:cheers:

In 4th gear, luggint at 1500 rpm (not cruising rpm) I get 10psi of boost, when I hit 2000 rpm with the skinny pedal down, I'm at 14.5 psi which is what really makes the difference. Just try chaning your settings, just a bit, it really does make a large difference. I use to think 10psi of boost was the cats meow but honestly it's only just starting to wake your truck up. I know, there are many who are worried about dropping pre-cups and cracking heads, but the thing that will tax the metals in our engines is the heat more so than the pressure. So you got to really watch the EGT's AND the pressure, quick bursts of higher boosts at lower EGT's will be fine as long as we don't hold it there, that's what's going to kill the engine....

Anyway, boosting right along :)
 
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IMO, 5th gear will become useless other than downhill with a tailwind.

I find it necessary to downshift from 5th to 4th on a slight incline or strong headwind in my turbo BJ42 on 33s w/4.11/H55.
 
first off, no one has 3.73 stock gearing in their Land Cruiser. it is 3.70, your not driving a jeep.

now, 3.70 with 33s skinnies will be fine on the flat but on that run every day you will start to hate the setup.
personally, i like the 3.70 for a DD/highway cruiser. fuel mileage is better, the engine runs quieter, replacement diffs are cheap since no one else seems to like them.
but
you will be wanting a turbo soon. i would suggest you go buy a nice condition set of used 31 skinnies for on the highway and save up for the turbo. once you have the turbo installed then purchase the slightly bigger 33s.

that would be the route i would take.

but

in reality most 33s are actually 31.5" tall and if you do run the 33s skinnies you will see a SLIGHT change in performance. if you run fats then you will see a more drastic change.

borrow a set off a buddy and take them for a quick spin up the hill and then make the call...
 
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