It depends, maybe if its build on swamp it would.

All late 928 manual boxes are unbelievably expensive to buy and fix.

 

Adam (or Steve), can you expand on this??

 

Erkka, thanks a lot for your assesment and the very illustrative photos. You really shed light on this toppic!!!

I will find out about the availability and prices of the GTS-pump solution tomorrow.

Actually the idea to fit the GTS oil pump was also the advice of a friend who runs a porsche garage. Only he did not know if it was really done with the rear cover the pump and the cooling line. So I called the guys from the Porsche Motorsports Department. They checked with a technician, called me back and said, that it wouldn't be possible because of the gear spray line as well as the fitting of the pump itself. But the latter appears to be nonsens.

Still I have two questions:
1. Are you sure that the huge cogwheel (that drives the pump) is really already fittet with my differential? (91 GT)
2. Where is the outlet line (from the pump) located on the back cover (do you by chance have a picture of that as well)?

It would be interesting to find out in what the back covers really differ. When I consulted my PET for the 91 model year I found the part number 928.301.306.00 for Models until 90 and this one 928.301.306.06 for 91 and up models. But if I choose the 92 model year in the first place I get yet another number 928.301.306.04.

Anyway thanks a lot for your help so far.

 

Anyone have any further information of suitable AMG-gearboxes? Which could be used to give internal parts...

Which standard Merc gearbox is similar to ´88 928 S4 4-speed auto?

 

Obviously they are right about spray bar, sort of. I think it would be possible to modify older casing and other parts enough to make line work.

Its also possible that pump doesn't work either without modifications. There might be problem in its pickup if GT box casing floor is higher at center at back than in GTS box. This would mean there isn't little space between pump pickup and aluminium below it for oil to be sucked into pump. If you look at below picture, pump pickup is positioned at low point in bottom center. If GT box do not have equally deep drop in there then pump mounting on rear cover would need to be lifted or pickup modified a little in order for it to fit. There is some drop in GT box but it could be that its not enough deep and/or long.



Gear is not there. Instead of it, you have version without teeth but its othervise similar. So you need to get gear part and possibly lock plate which is used to lock it to differential housing fit old is not reusable.

Outlet channel from pump to hose is cast into rear cover. It comes out from upper corner of cover through banjo bolt as shown in below pictures.





Difference between two GT versions is that later variant do not have preparation for speed sensor magnet mounting on outside. Basically its missing one small threaded hole for mounting bolt. Or at least thats what I think is only difference between two.

 

Most likely AMG Hammer gearbox and what ever later V8 and V12 AMG models which used 4sp gearbox.

 

Randy,

Is there any chance of pulling the GTS/manual external oil cooler posts out of this thread and putting them in a separate thread. It's valuable information that will get overlooked due to the title of the original posting. Also, it interfere's with the thread on the original post.

 

More manual gearbox oil pump discussion with trial fit pics in here:
https://rennlist.com/forums/928-forum/333486-gts-manual-gearbox-oil-pump-into-automatic-differential.html#post3917159

 

So how much to send the complete GTS trans in pieces to the states

 

A28/ 4Speed transmission can easily handle 500Ft lbs of continuous torque and 850 FT Lbs of momentary torque. There are no Kits; parts needed are order from MB individually. Parts are about $3000 USA. Then there is knowledge and experience which one acquires after many failures to put it all together


Scott M. Quote:
Originally Posted by atb
Hi Stefan,

Steve C. gave me the following advise (sorry no AMG part #'s) several years ago in preparation for my stroker build:

"...Disable the rear pump, in the transmission, its only purpose is to push
start your car. It has a history of failure."


He lurks on the list, hopefully he'll have some additional input.




Adam (or Steve), can you expand on this??


The rear pump was deleted in all Mercedes Benz transmissions in 1991. The check valve spring in the valve body would break and fined its way into the Secondary pump, causing a pump or governor failure. The governor drives the rear pump. MB makes a pump elimination kit.

 

Steve,

Can you give a ball park on your labor to install the AMG parts. (Assuming the tranny is crated and shipped out to you).

Thanks.

 

Steve,
I'm interested to
Thanks.

 

So a pre '91 4spd auto can be push started? OMG!!!

 

Also try a search, Steve's sig line listed mods and who did them.
Maybe someone will chime in with one of his posts.
Also call Greg Brown at Precision, I know Greg did a lot of Steve's work.

Good Luck!