99 Isuzu Trooper on 35s? Will they fit?

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Rorschach

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Oh yes! If you could look into the interchanges that would be a big help. Independent4x wants 650$ for a 4:77 third member, but if I could find one at a junkyard that would save me some.
Thank you
Bad news is there is only one gear ratio from the factory from 02 on, 4:3.1. Only option available was limited slip or open diff. The gears and carrier from the later 98-02 (UY) Troopers are different from the earlier 92-97 (UX) Troopers. This is due to the size of the ring and pinion as well as the carrier. I checked to see if the VehiCross and Axiom would interchange as they had Trooper drivelines, but they don't. They are newer and had the same ratio as the Troopers anyway. I checked the Rodeo, but it has a different axle manufacturer so no good, lot of gear options though. And just cause I could I checked the 86-91 (KT) Trooper. No good here either. I was talking to someone in R&D and he has a gear supplier he is going to get me the name of. When I get that I will pass it on.

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Rorschach

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Rorschach, that great you work for Isuzu. I can you get Isuzu parts from other countries? I know the part numbers for just about every gear that will fit in our troopers.

The 4.77 gears are very hard to find in a junkyard, and it's alot of work to remove. Also, in my manual it shows the 99 Trooper has the "mod 12-bolt rear" it's actually a bigger ring gear than the normal 12, but the biggest gear and that fits is 4.30. so to use a 4.56 or 4.77 you would need to swap the entire 3rd or axle to make it work.

If your dead set on having 35s on your Trooper it's possible but it's alot of work to keep the drivability there.
I have never tried. I have put out the question and am waiting on a reply.

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Rorschach

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Rorschach, that great you work for Isuzu. I can you get Isuzu parts from other countries? I know the part numbers for just about every gear that will fit in our troopers.

The 4.77 gears are very hard to find in a junkyard, and it's alot of work to remove. Also, in my manual it shows the 99 Trooper has the "mod 12-bolt rear" it's actually a bigger ring gear than the normal 12, but the biggest gear and that fits is 4.30. so to use a 4.56 or 4.77 you would need to swap the entire 3rd or axle to make it work.

If your dead set on having 35s on your Trooper it's possible but it's alot of work to keep the drivability there.
I am checking. What country and what type of parts?

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Classic City Overland

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So this has been discussed in detail on the PlanetIsuzoo forums, I'll see if i can find the write up. Its because you have the "modified 12-bolt" vs the "normal 12-bolt".

Anyway, You can swap out the entire rear axle from the 94-97 Trooper and it will mount the same, use your oem links and springs and all, I think the axle input is the same aswell. Its just the overall axle width is different, slightly narrower, so to maintain your current stance you may need to use a set of 1" wheel spacers to offset your wheels the same.

The 2nd gen rodeos/Amigo all have a special Dana 44 in the rear and wont work. The first gen (pre-92) Trooper axles are 12 bolts and have 4.56 gearing but use leaf springs and wont work without alot of welding and fab work and they are even narrower.

Like I said previously, its alot of work to make 35s work on any Isuzu suv, and it really hampers the drivability and ride quality. From my personal experience with I wouldn't go through all the work to make it happen. I have a 94 Trooper with the 3.2 (read as 175hp) SOHC v6, with 4.56 gears. It is not really that peppy with 33s but at least i can use 5th gear. I would bet with 35s, it wouldn't even pull in 4th going up a hill.
 

Classic City Overland

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Rorschach (cool name BTW),

Heres the parts i'm looking for to see if they are obtainable. They were used in several overseas Isuzu (pickups) in austrailia/thailand/ maybe south america

Isuzu part#s

8980135931 (alternative "old" part# 8972204001 ) - 41/8 final drive gear set
8973588240 - 43/9 final drive gear set (8944353170 maybe an alt. part #)
8971824040 - 43/9 later model 10-bolt

Any help getting these parts would be greatly appreciated.

Pics of my Isuzus just for kicks.

IMG_20170923_173043.jpg
IMG_20170311_142906.jpg
Eric
 

Kirill Rudnev

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Rorchach
Thank you for the info, like Eric said, having the modified 12 bolt for the limited slip narrows down the gearing options to 0, but you could thill swap out the whole third member from an older one. Right?
 
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Rorschach

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Rorchach
Thank you for the info, like Eric said, having the modified 12 bolt for the limited slip narrows down the gearing options to 0, but you could thill swap out the whole third member from an older one. Right?
Pumpkins won't swap, I checked for this. As Classic City Overland says, if you really want it you will have to do an axle swap or get aftermarket gears.

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Rorschach

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Off-Road Ranger I

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Huntington Beach, CA
First Name
Robert
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Niederhauser
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KM6ULA
Rorschach (cool name BTW),

Heres the parts i'm looking for to see if they are obtainable. They were used in several overseas Isuzu (pickups) in austrailia/thailand/ maybe south america

Isuzu part#s

8980135931 (alternative "old" part# 8972204001 ) - 41/8 final drive gear set
8973588240 - 43/9 final drive gear set (8944353170 maybe an alt. part #)
8971824040 - 43/9 later model 10-bolt

Any help getting these parts would be greatly appreciated.

Pics of my Isuzus just for kicks.

View attachment 36035
View attachment 36036
Eric
Thanks, I haven't forgotten you. I've been buried with a project at work and have not had the chance to follow up. I will tomorrow.

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Classic City Overland

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Thanks, and as for the question, No indy4x sells 3rd members but they you would need to swap the entire rear axle with an earlier style one. And if you call some junkyards or pul yards they are readily available from earlier model troopers and they will come with 4.56s installed and some of those are LSD models. The whole axle is pretty easy to pull and they are cheap, sub $200 at most yards. but realize you need to match the front and rear and the front is a bear to get out. and almost impossible in a junk yard.
 

Classic City Overland

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Yes, that is correct. Everything else is the same up front. I have several "write ups" on replacing he front 3rd member on the other forum. Its a fair amount of wrenching, takes me about 3 hrs to get it all out and back in. And I've one it 3 times.