Relative strength of transfer boxes and which transmission to use with 4bd1t?

[headdamage]

I understand that the LT95 is stronger than the LT85 and the R380, at least that seems to be the majority opinion.

What I'm now wondering about is the transfercase part of the LT95 vs the LT230. My suspicion is that the LT230 might be the stronger box with the right gears set and perhaps an ATB center diff. I'm interested in the ATB diff due to my living in an area with a fair amount of snow and ice covered roads for a few months of the year.

I have a 4bd1t and an LT95a which where sold to me as being in good condition with only 50,000 miles on them. I like the LT95 on paper but have never driven one and parts seem to be scarcer than those for the other options. For example it is easy to order an LT85 or R380 from the UK and the shipping is not too bad to here in Canada. The LT95a is a bit of a rare item here and in the UK. The shipping from the land down under is a bit steep, not that the LT95a is very common to find from what I've seen on the internet so far.

I'm temped to just use the LT95a and deal with it as best I can if it fails at some point but I also have a few LT230 boxes kicking around and a friend has a couple of good LT85 boxes he'll trade some other Rover stuff for. From another source I have been offered an Isuzu to LT85 bellhousing.

Another factor is that I'm considering fitting the 4bd1t into my exmilitary 90 (currently has a good 200tdi and LT77/LT230 in it). To me the LT85/LT230 combo seems like it might be a good fit for the lighter 90. On the other hand, if I decided to put the 4bd1t into a 110 I'm leaning more towards the LT95a for strength assuming the LT95a transfer case is similar in strength to the LT230.

Sorry if this is rehashing the topic but I've spent a lot time on here reading everything I can find and am looking for some additional feed back.

Thanks.

[Phil B]

I’m sure Bearman will be along soon but the reliability of the LT95a depends on regular servicing with the right oil and being set up correctly when it is repaired/ overhauled.
Great combination with the 4bd1 as well. That why the ADF ordered them but they are all close to 30 yrs old now and you need to consider that they have all be opened at least once IMO.
Get the box checked by somebody who knows them before you put it in would be my advise.

[headdamage]

I would likely have to send the LT95a overseas in order to have it looked at by someone that really knows them. I is a very uncommon transmission in North America. I know of two (including mine) within a 500km radius and the closest shop, that I know of, that would know what one was is about 1000km away (not that they want to touch one, they haven't had good luck fixing them apparently).

[Phil B]

I would likely have to send the LT95a overseas in order to have it looked at by someone that really knows them. I is a very uncommon transmission in North America. I know of two (including mine) within a 500km radius and the closest shop, that I know of, that would know what one was is about 1000km away (not that they want to touch one, they haven't had good luck fixing them apparently).

Sorry. I should have looked where you are.
I suggest you PM Bearman on here and ask him how you can test or check the LT95 without having to send it away.
Good luck with it.

[Standard]

I understand that the LT95 is stronger than the LT85 and the R380, at least that seems to be the majority opinion.

What I'm now wondering about is the transfercase part of the LT95 vs the LT230. My suspicion is that the LT230 might be the stronger box with the right gears set and perhaps an ATB center diff. I'm interested in the ATB diff due to my living in an area with a fair amount of snow and ice covered roads for a few months of the year.

I have a 4bd1t and an LT95a which where sold to me as being in good condition with only 50,000 miles on them. I like the LT95 on paper but have never driven one and parts seem to be scarcer than those for the other options. For example it is easy to order an LT85 or R380 from the UK and the shipping is not too bad to here in Canada. The LT95a is a bit of a rare item here and in the UK. The shipping from the land down under is a bit steep, not that the LT95a is very common to find from what I've seen on the internet so far.

I'm temped to just use the LT95a and deal with it as best I can if it fails at some point but I also have a few LT230 boxes kicking around and a friend has a couple of good LT85 boxes he'll trade some other Rover stuff for. From another source I have been offered an Isuzu to LT85 bellhousing.

Another factor is that I'm considering fitting the 4bd1t into my exmilitary 90 (currently has a good 200tdi and LT77/LT230 in it). To me the LT85/LT230 combo seems like it might be a good fit for the lighter 90. On the other hand, if I decided to put the 4bd1t into a 110 I'm leaning more towards the LT95a for strength assuming the LT95a transfer case is similar in strength to the LT230.

Sorry if this is rehashing the topic but I've spent a lot time on here reading everything I can find and am looking for some additional feed back.

Thanks.Hi headdamage,

Are you set on keeping it Land Rover only?

If not, then maybe an NV4500 5 speed. It's strong, easy parts availability in North America and it's slightly shorter then an R380.

Roamerdrive make a belhousing;
BELL HOUSING ISUZU 4BD1 4BD2 | eBay (https://www.ebay.com/itm/BELL-HOUSING-ISUZU-4BD1-4BD2-/254276686594'redirect=mobile)
(they have put an Isuzu and NV4500 into a 101 forward control)

Advance Adapters and a few other places do an NV4500 to LT230 adapter kit
50-9000 : Jeep NV3550 / Dodge NV4500 with 23 spline to Land Rover Transfer Case Adapter Kit | Advance Adapters (https://www.advanceadapters.com/products/50-9000--jeep-nv3550--dodge-nv4500-with-23-spline-to-land-rover-transfer-case-adapter-kit/)

Cheers,
Stan

[Bearman]

I understand that the LT95 is stronger than the LT85 and the R380, at least that seems to be the majority opinion.

What I'm now wondering about is the transfercase part of the LT95 vs the LT230. My suspicion is that the LT230 might be the stronger box with the right gears set and perhaps an ATB center diff. I'm interested in the ATB diff due to my living in an area with a fair amount of snow and ice covered roads for a few months of the year.

I have a 4bd1t and an LT95a which where sold to me as being in good condition with only 50,000 miles on them. I like the LT95 on paper but have never driven one and parts seem to be scarcer than those for the other options. For example it is easy to order an LT85 or R380 from the UK and the shipping is not too bad to here in Canada. The LT95a is a bit of a rare item here and in the UK. The shipping from the land down under is a bit steep, not that the LT95a is very common to find from what I've seen on the internet so far.

I'm temped to just use the LT95a and deal with it as best I can if it fails at some point but I also have a few LT230 boxes kicking around and a friend has a couple of good LT85 boxes he'll trade some other Rover stuff for. From another source I have been offered an Isuzu to LT85 bellhousing.

Another factor is that I'm considering fitting the 4bd1t into my exmilitary 90 (currently has a good 200tdi and LT77/LT230 in it). To me the LT85/LT230 combo seems like it might be a good fit for the lighter 90. On the other hand, if I decided to put the 4bd1t into a 110 I'm leaning more towards the LT95a for strength assuming the LT95a transfer case is similar in strength to the LT230.

Sorry if this is rehashing the topic but I've spent a lot time on here reading everything I can find and am looking for some additional feed back.

Thanks.
G'day mate, The LT95 has physically bigger gears than the LT85 and R380 and while some people have had a good run with these boxes behind the Isuzu motor it it generally accepted that the LT95A is the best land rover box behind this motor apart from an Isuzu truck gearbox. The LT95 is a 1 piece gearbox/transfer case whereas the other 2 have bolt on LT230 transfer cases. There is nothing wrong with either transfer cases in my opinion, both are similar strength, in fact the centre diff has the same gears/shafts in both of them. I have used both but still stick with the LT95a as I like the gearbox and if set up properly it will last for years. 4th gear is good for 40k to 140k/hr. Once you get into 4th gear you rarely have to downshift even overtaking or going up hills and there is not much difference in engine revs between them. The tapered roller bearing intermediate shaft in the LT95A is a must behind this motor (especially if it is turboed). Parts are not a problem for these boxes in Australia and the UK. I think it was me that offered the LT85 bellhousing to you on FB. Cheers...Brian

[rar110]

Bearman - the LT95 whisperer. [emoji38]

Mal Storey did a mod for the LT85 to make it more robust against the 4BD1. But those boxes would be rare now.

I had 110 with a factory 4BD1 matched to a LT85. The box failed a few years after I sold it (not sure why) despite the R380 output shaft lubrication style mod.

I’ve had a 110 with the LT95 since 2006. Interestingly I decided to test drive a Puma 110 with a 6 speed. I hated it.

The combination of a turboed 4BD1 with a LT95 is a pretty easy drive. The blown 4BD1 torque means the gearing/ratios are very drivable. I recently bought a D1 with a 300tdi with a R380. It’s a nice combination. But even my 15 year old recognises how easy the blown 4bd1 is to drive because of the elevated torque levels at low revs.

Just my experience.

[tc_s1]

I have both behind different 4bd1's. I modded the lt85 by adding a stronger synchro ring pin than standard, as often the originals (and stock replacements) will shear over time. Thankfully the lt85 has been a great box since then. From what I experience driving them each weekly the lt95 does seem a more sturdy/robust box and I have no issues with it whether rolling iver rocks or down an interstate. The way mine are setup I have a bit more revs at the top end with the lt95 than using overdrive on the lt85, but it's not a problem for either. Admittedly I won't drive 140kph even though they are capable......they are rovers and at that speed one needs more considerstion given to braking than gearing. [emoji16]

[headdamage]

Well then if the transfercases are not significantly different in strength but the main boxes are then the LT95a is looking like the way forward.