Mud-club

Vehicle & Technical => Defender => Topic started by: themudmurderer on January 21, 2004, 10:30:55

Title: lt77 gearbox
Post by: themudmurderer on January 21, 2004, 10:30:55

Im going to be putting a v8 in one of my 90's. it has an lt77 which was originaly connected to a 2.5 na.will it fit straight on???
mike

Title: lt77 gearbox
Post by: Ben on January 21, 2004, 10:36:30

Not sure the lt77 will take the extra bhp through it. Might be better with an lt85.

If it's the blue 90, I'm not sure how strong a gearbox that's done 110,000 miles without a rebuild that's been stood for a year will be...

Cheers

Ben

Title: lt77 gearbox
Post by: themudmurderer on January 21, 2004, 10:38:55

good point.although the v8 probably isnt that different to the diesel as it doesnt have as much torque.

Title: lt77 gearbox
Post by: Ben on January 21, 2004, 10:50:38

Fair one...

I'm not sure why they didn't put the lt77 onto V8's as standard on the early 90/110's though... They still used the 4 speed manual at the time, when the diesel had moved onto 5 speed with the lt77.

Someone must have done it though - have you asked on (dare I say it) LRO?

Cheers

Ben

Title: lt77 gearbox
Post by: muddyweb on January 21, 2004, 13:07:51

The LT77 from a 4 cylinder engine won't fit straight on a V8.

There is a variant of the LT77 which was used in the Range Rover... it's normally referred to as a 'Longstick' Variant.  This will go straight on the back of a V8.  

On a 3.5 V8 you will probably be OK for a while.    I have been running LT77 boxes in my 90 (4.0L GEMS V8 ) and it's just eaten the second box in 18 months.

The LT77 is not a particularly strong box.


The LT85 is stronger, but are hard to find and expensive.  Again, this should be a reasonably simple fit.

The LT95 is the 4 speed box as used in 110 V8 and earlier Range Rovers.  These are very tough... but not as pleasant to drive.

If you have a 4 cylinder LT77 box which is reasonable, your best bet would be to get a conversion kit to fit it on a V8.  The boxes are reasonably easy to get on the second hand market if it fails, and will be cheaper to repair than any of the others.

If you could find one for decent money, the R380 is a much better box... but they are expensive and did tend to have trouble with poor bearing lubrication on the earlier units.  (again, the diesel and V8 variants are not directly interchangeable)

I am in the process of putting an auto box in mine... I can't be doing with breaking gearboxes every 18 months... it's too expensive :cry:


Give QT services a call for a conversion kit to fit an LT77 to the V8...  Dave will be able to sort you out with the right bits.

www.qtservices.co.uk

Hope this helps.

Title: lt77 gearbox
Post by: themudmurderer on January 21, 2004, 14:13:24

thanks for the info.
mike

Title: lt77 gearbox
Post by: ChrisW on January 21, 2004, 22:51:10

Mike, what happened to the 2.5NA, just out of curiosity, not that I've got any money to spend on one or anything like that!

Title: lt77 gearbox
Post by: themudmurderer on January 22, 2004, 10:35:04

someone is buying it. so as i have a load of v8 lying around i thought i would put one in.
mike