Rear differential with Haldex 3 OVERHAULED:
Land Rover Evoque
M14x1.5 Another one delusion
It seems to be a popular fallacy in the north (UK and Scandinavian) that E30 has M14x1,5 on the crown gear bolts. Each typ188 has bolt size M12x1.5.
I have been doing with differentials for years. The only differential type188 with M14x1.5 I’ve ever met is the BMW E36 M3 3.0. Also in the official documentation of BMW is invariably present thread M12x1.5 of gear ring bolt.
Here is for sale LR transfer box:
Genuine Transfer Box
General inspection: A properly reassembled car part. The article was completely disassembled, cleaned and examined for wear and tear.
A new oil seal to the input shaft of the transfer box.
High/low range selector and lock selector work properly.
Gears have no signs of wear.
No oil inside.
transfer box oil grade 90W
As we know at BMW rear wheels are driven. BMW chose to use LSD friction type produced by ZF. All BMW models until E36, E34, E32 could be produced with the option “LSD”. Over the years, they were installed and other types as Visco LSD, locking type (EH Differential), Torsen… but this was as an exception.
Here I will explain what is the difference between open differential and LSD. Differential character is determined by planetary gear. This mechanism is designed to differential case. Here is an example of open case type and limited slip case.
The main problem of the open diff is the loss of traction. When one drive wheel is in the air or on ice or road surface with different grip, the car loses it mobility and power. Rotates only the wheel which has no traction. Americans call this effect (or defect) “one wheel peel”. Anyone who has driven a car has experienced this defect, even if he did not know that’s is happening. I personally find it very unpleasant. But I’m not impartial. Limited slip differential (LSD) can transmit a certain torque to the wheel that got traction.
This can be done by using friction discs (#9 in the picture), installed in LSD case:
There is a lot of practical advantages when we talk about LSD. At first, the limited slip differential is very useful in poor road conditions such as snow, mud… LSD makes possible different road performances, donuts and having a lot of fun . The fun is guaranteed if you decide to take a turn sideways. As a man who enjoys sports driving and track racing LSD is necessary, and when it comes to motor sports is MUCH needed. This applies not only to drift, but for all track and rally disciplines. In drag racing, for example, the presence of LSD makes the start much better. The things can be almost perfect…
It is possible to make LSD with an higher percentage lock and a different gear ratio, according to the field of application.
The most amazing thing about LSD is the fact that it works completely automatically. Don’t need any human intervention, pressing buttons, etc. As someone says: self-blocking differential. However it requires a little more attention to service. If in the open diff not fundamentally change the oil (Long life), the limited slip differential requires a special oil, which must be changed frequently, depending on how you use the car and what is the main purpose.
Normally the cars are equipped with open differentials, just like cars with rear wheel drive, differential case (differential briefly) and final drive (gear pair) are placed in one housing.
Front wheel drive cars have even 3 in 1. Differential, final drive and gearbox. Open differential is the cheapest and easiest to maintain, so it’s preferred for OEM.
Hypoid gear is among the most important innovations in the automotive industry in the twentieth century. On February 8, 1926 the Packard Car Co. for the first time in the world used hypoid final drive. This innovation Packard would not have been possible without the development and improving of the company Gleason Works, Rochester, created lathes for cutting hypoid gears. Thanks to this cooperation eliminating howling gears in cars. Today this unusual sound can only be heard when driving a car in reverse on manual gearbox, where as before are used gears with straight teeth, and in some racing gearboxes.
In hypoid gears, unlike other bevel gears, the axes of the ring and pinion do not intersect in one plane and not fits geometrically, they cross.
Due to that form of extended contact area of the teeth of the two gears, it is possible to make larger and stronger, which allows the transmission of more force in gear. The transition the axis of the pinion below that of ring allows to lay drive shaft down, to lower the center of gravity and make the floor in the car equal. Hypoid gears is quiet and has a high efficiency and therefore remains irreplaceable already 90 years.