Supplemental Information & FAQ for MG T Series 5-Speed Conversion Kits

Which 5-speed gearbox is being used?
The Ford T-9 gearbox as fitted to the European Ford Sierra. This gearbox also
appeared in the US in the Mercury Merkur.
Is the gearbox new or rebuilt?
The gearbox supplied with the Moss Motors 5-Speed Conversion kit is rebuilt in the UK. It is covered by our extended 24 month warranty.
Are rebuild parts for the gearbox going to be available in the future?
The T-9 gearbox is extremely durable so it is unusual for a box to require major repair. Usually seals and gaskets are all that is required for a long service life. The gearbox is very popular for conversions and kit car use, so parts availability should be excellent for many years. The T-9 case design has become the European standard for 4 cylinder rear engine conversions and although the transmission is now out of production, there are specialist companies manufacturing new look alike units to meet the needs of the market.
Where can I buy parts for the gearbox if I need them in future?
Moss Motors will stock the seals and gaskets that may be needed during removal and inspection of the gearbox in the future.
How can I tell if my TD has a 7 1/4” Clutch or 8” Clutch?
Vehicles fitted with the 7 ž” clutch have a 5/8” (15mm) cross shaft
Vehicles fitted with the 8” clutch have a ū” (19mm) cross shaft
The diameter of the original cross shaft determines which Moss Conversion kit to order. The differences between the TD conversion kits are the bell housing and clutch disc, so it is critical that the cross shaft be measured before ordering a kit.
Will my speedometer be accurate?
No. You will have to either recalibrate your speedometer, or install a corrective gearbox on the speedometer cable. Moss Motors is working with a number of speedometer repair companies to source such a unit.
What are the gear ratios of the new gearbox?
The gear ratios of the Ford box are very good match to the original gear ratios offering the best balance of low starting gear and an 18% decrease in engine revs in 5th gear.

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