Types of gearbox found in MG ZR's

[rakester]

I see a few threads crop every now and then about gearboxes, here is a brief rundown of what gearboxes came in ZR's and the pro's and con's of each one.

Types of Gearbox Found in Each Model

MG ZR 1.4 105

'R65 Gearbox' - Found in all 1.4 105 MG ZR's up until mid 2003 (meaning the R65 is only found in MK1 Zr's) and up to the VIN number '3D 720773'. Considered the weakest gearbox and generally the type that breaks most often.

'IB5 Gearbox' - Found in all 1.4 104 MG ZR's from mid 2003 onwards (and ALL MK2 105's) , any VIN number past '3D 720773' will have an IB5 gearbox. Derived from a Ford zetec gearbox, considered to be a very strong gearbox and much better than the R65.

MG ZR 1.8 120 and MG ZR 1.8 160

'PG1 Gearbox' - All MG ZR 120's and 160's regardless of year/model use the PG1 Gearbox. Considered a strong gearbox on a standard car.

MG ZR 2.0 Diesel 100 and 115

'PG1 Gearbox' - All MG ZR diesels regardless of year/model use the PG1 Gearbox. Considered a strong gearbox on a standard car.

Service Intervals

R65: Oil should be changed in the gearbox every 105,000 miles or 7 years (whichever comes sooner). The recommended gearbox oil for this gearbox is Castrol EPX 75w/80 GL-5 gear oil, the box takes 1.8 litres

IB5: Oil should be changed in the gearbox every 105,000 miles or 7 years (whichever comes sooner). The recommended gearbox oil for this gearbox is Castrol BOT130M gear oil, the box takes 2.0 litres

PG1: Oil should be changed in the gearbox every 105,000 miles or 7 years (whichever comes sooner). The recommended gearbox oil for this gearbox is MTF94 gear oil, the box takes 2.2 litres

* gearbox oil changes should take in other factors, oil should be changed sooner if you drive the car hard or track with it. These are only recommendations based on reliable sources of information.

[petrol-head16v]

Great post mate

[Propower]

Awesome post, nice one!

[dazlamb10]

Great info jake

[Levaz]

Do all the gearboxes use the same driveshafts?

I think my R65'd ZR needs a new drivers side one, but can't find any specific details on it.
Also, are the ABS/non-ABS shafts different?

[shellz47]

hiya I have just got a r65 gearbox for 03 zr 1.4...105 model......as mine was noisy...my son who is a full mechanic fitted it and realised the selector arm is bent...altho the spline shaft seems solid ..no play like mine in it....we still here noise other than before we changed it.... am gutted and trying to get a replacement from mgrover spares ...ordered through partsgateway....I am trying to pick anyone brains on this...he did consider straightening the arm. .until tried it and heard noise....if anyone here has used that scrap yard??