Towing and Performance Upgrades

1. Why do I need to know about upgrade options?
If serious four wheel drive activity, including beach work, towing camper trailers or vans or increasing engine outputs is anticipated, there are durability improvements and upgrades available for most Domestic, European and American transmissions.

The grey nomads want their vehicle to be more suited to the job at hand such as towing their large van and gaining peace of mind as a result. Remember the manufacturer does not have the need to tow as a major consideration when he designs the vehicle.

Another example is someone buys a 4wd and adds large tyres and wheels, bull bar, winch, lockable tool boxes, long range tanks and probably just added a minimum of 500kg to the weight of the vehicle and in so doing is adding the equivalent of a trailer in terms of load to the transmission and cooling system.

2. What are the benefits?
Increased reliability under heavy loads. Transmissions run cooler in the cases where additional heat exchangers are fitted. Remember, extra loads for the vehicle equal extra heat. Heat is a real enemy for automatic transmission seals and oil life.

3. Can these improvements be done without reconditioning my transmission?
Increased clutch capacity can only be achieved when the transmission is stripped on the bench although there are quite a lot of improvements to the hydraulic control systems that can be done on a service. These upgrades/modifications can have quite dramatic improvements depending on the particular transmission involved.

4. Can you give me an example?
Lets take a 1970 Mustang muscle car restoration. How would you like to have total control over the shift points up or down at any speed and yet be able to have regular shifts when left in drive? This is possible with valve body reprogramming. Naturally it is advisable to know the transmission internals are in good shape because of age.

A later vehicle upgrade would be a Land Rover Discovery in for a transmission overhaul where both sprag clutches (Mechanical one way freewheel units) are replaced with later and stronger units and an increase in operating pressure.

A Ford F250 owner who wants to tow a van will be offered a billet convertor, increased clutch capacity, valve body mods to increase operating pressures and volume of apply oil to internal components and in some cases optional temp gauge kits for the owner to monitor the transmission together with deeper oil pan to increase oil capacity.

Landcruiser Transmissions
A440, A440F, A340, A442F, A450-43LE Extra oil cooling by way of larger accessory cooler. This can drop the trans temp by as much as 10 degrees centigrade. Coolers with their own fan and shroud are available Valve body overhaul resulting in increased line pressure and cooler flow. These valve bodies suffer from warpage due to heat. A change to synthetic fluid can also result in an operating temperature drop of 5-10 degree centigrade range. Lifting stall speed to allow for larger tyres. (Relatively small tyre changes only) Transmission temperature gauge.

GM Transmissions
TH700R4, 4L30E, 4L60E, 4L65E, 4L80E, TH350, TH400, 5L40E, Hydramatic, Powerglide, Trimatic. Extra coolers Kevlar based friction materials Valve body recalibration Larger servo for greater band clamping force Synthetic oil Higher stall convertor Transmission temperature gauge

Range Rover/Landrover, BMW, Mercedes, ZF transmissions
ZF3HP12, ZF3HP20, ZF4HP22, ZF5HP30, ZF6HP26, Mercedes 722 series. VW003, VW010, VW01N, VW01M, VW01P, VW09G, VW09K, TF60SN. Range Rover Up graded* gear sets and free wheel units (Sprag clutches) are available for these transmissions. Some of these are able to have ratio changes which may prove beneficial for rock climbing. Extra coolers. Synthetic oil. Transmission temperature gauge.

2 speed, C3, C4, C6, BW35, BW40, BW65, M85, M91, M95, M97, 4R100, E40D, BW M8, BW M12, AX4N, A4LD Ford F truck series Transmissions Ford have limited the torque output of their diesel engine to make it easier on the transmission. This makes the chip manufacturers look good as they unleash extra torque and horsepower, but the transmissions fail more easily as a result.
There is a host of upgrades* available to make this unit perform more reliably than a factory unit especially when towing. Extra cooling, synthetic oil, valve body recalibration and temperature gauge applies.

Dodge Ram/Chrysler Jeep Transmissions
45RFE, 545RFE, A404, A500, A518, A618, A604, A606, Powerflite, A904, A727 A repeat of the F series situation and again there is a host of upgrades* and improvements available. Extra cooling, synthetic oil, valve body recalibration, and temperature gauge applies.

3N71B, 4N71B, F3A, F4AEL, F4EAT, G4AEL, RE4F02A, RE4RO1A, RE4FO2A, N4AEL Nissan Patrol These respond well to valve body reworking for increased line pressure and convertor lock up performance. Extra cooling, synthetic oil, and temperature gauge applies.

*Upgrades refer to modifications to vehicles outside of the manufacturers specifications and warranty period. We do not infer the vehicle manufacturer’s product is inferior, but rather offer ways to improve the transmission life and performance beyond the warranty period based on 35 years of practical transmission repair experience. Vehicle manufacturers prioritize drivability and comfort of gear shift feel (soft shifts). Upgrades often result in firmer shifts as clutches, bands apply faster and with more clamping force.

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