My Experience with 5 speed conversion

[Vincent Hor]

Just to share my experience on the conversion of the 4 speed GM auto gearbox to a Jatco 5 speed on my E34 M50B25. Reason for the conversion was symptoms of a failing torque converter. Hopefully this will give some confidence to some of you who are thinking along this route. Thanks to Albundy and Kevster whose positive advise help me in my decision making. The job was handed to my regular mechanic Albert Fang of WP Auto in Pandan Indah. I must say that he knew exactly what to do and there was absolutely no hitches at all. I also took the opportunity to replace the flywheel oil seal. It seems like a plug & play job. The following were sourced from a Japanese half cut which has only clocked 87,000 kms 1. Jatco RE5R02A gearbox2. Longshaft3. Rear diff 3.914. Gear shifter mechanism & sensors5. Oil cooler & relevant pipings6. Gear box ECU with complete g/box wiring Albert just delivered back the car this afternoon. So far I am enjoying this new experience. The gear box seems more responsive through out the gears. It's running at lower RPM's compared to the GM 4 speed. 110 kmh is at about 2.2k RPM. According to Albert who tested the car last night, it was doing like 140 kmh at 3K RPM. Gear shifts also quite smooth. Although not tested yet, I believe outstation drives should yield better fuel consumption. Total cost RM3,700

 

[ALBundy]

Hi Vincent, great to hear the positive feedback

Cheers

 

[integramania]

Bro...thanks for posting ur experience here....

Sorry to post here but can I ask what does a faile torque converter feel like?

I have this symptom...i tested another e34 tats within the family...it feels more torquey than mine...is it the torque convertor being faulty? or is it that maybe that car has been changed its gearing?

Anyone can shed some light into this? Also if wanna improve the response can you change the internal gears?

Thanks

 

[Vincent Hor]

The symptoms as I was told by Ah Meng (M-Speed) which was a second opinion is a slight vibration just before a gear upshift.

Bro...thanks for posting ur experience here....

Sorry to post here but can I ask what does a faile torque converter feel like?

I have this symptom...i tested another e34 tats within the family...it feels more torquey than mine...is it the torque convertor being faulty? or is it that maybe that car has been changed its gearing?

Anyone can shed some light into this? Also if wanna improve the response can you change the internal gears?

Thanks

 

[Vincent Hor]

Update : So far car running very well. No idle issues and gear change is very smooth but stopping the car seems to need a bit more effort on the brakes.

 

[yusriyacob]

thanx for info bro....emmm 5 speed is more saver than 4 speed...the engine also is reducing the work...

 

[ramsing]

no no....u must go for 5 spd manual....if in doubt, u can check with Al Bundy. he likes to play with his stick one.. always leaves him with a wet feeling

but 5 spd auto is nice. sat in a 520i with 5 spd, feels lively and not underpowered.

 

[flash]

Had that same issue with my ex-SLOTH which has a 5 speed ZF gearbox as compared to another with the 4 speed GM one. Hmmm.... but yes, that extra gear ratio helps... at 3k, I was doing about 140kmh.

Update : So far car running very well. No idle issues and gear change is very smooth but stopping the car seems to need a bit more effort on the brakes.

 

[integramania]

The symptoms as I was told by Ah Meng (M-Speed) which was a second opinion is a slight vibration just before a gear upshift.

my gears shoft quite fine...dun feel the vibration....but i dunno why its like less responsive compared to the other e34....so far the other e34 is also stock

 

[pussy]

Inter.. received your PM...

You got mail..

 

[m43ldotcom]

First I read the title, I thought you change to manual

Congrats Vincent!

 

[Vincent Hor]

Bro, sudah tak biasa pakai manual!

First I read the title, I thought you change to manual

Congrats Vincent!

 

[longan]

huhuhu,.. oto also ok what.....
mr vincent.. hows top speed? try already?

 

[Vincent Hor]

Top speed? Never tried it (15 year old car already) but I am happy the car cruise quietly at 160km/h.

huhuhu,.. oto also ok what.....
mr vincent.. hows top speed? try already?

 

[june_yap]

still wondering what is the fuel consumption like after conversion.....?

 

[SuperCharger]

Hi Vincent, That price includes trading in your old gear box?

Did you have to source for the parts yourself or your mech got contacts?

 

[Vincent Hor]

The parts were sourced by my mechanic. Anyway, the chop shop is also my friend. I think the mechanic has the experience to select the better condition items.

My GM 4 speed is still in good condition. Left it with my mechanic. If anyone takes it (cheap 2 only) then he will give me some value lah.

 

[Vincent Hor]

Update : RM120.00 = 370kms city driving
Petrol price : RM2.55/litre
Works out to be 7.86km/litre or 32-33 sen/km

still wondering what is the fuel consumption like after conversion.....?

 

[june_yap]

Update : RM120.00 = 370kms city driving
Petrol price : RM2.55/litre
Works out to be 7.86km/litre or 32-33 sen/km

very good consumption....
i think waja pun kalah...

 

[integramania]

Just wanna ask...525s ard that FC (30cents+ per KM) is considered very good consumption?