pilot bearing # for 4-sp swap
 

I have been up and down the manual trans swaps threads. Anyone ever find a part number to put the early (mine is a 79) 240 4-sp tranny into a later (1985) 617 engine?

Peter

You will have to make a bushing for it, get a custom sized bearing or have the crank bore machined to fit the stock bearing.

AFIK, you and TomJ are the only folks that have encountered the odd sized late model crank. TomJ went with an undersized bearing OD and machined a brass/bronze sleeve to make up the difference. You could also have a bushing machined from oillite bronze similar to what older US cars used.

RLeo--

I haven't seen the offending member yet, just assembling parts (just remembered that I have to figure out the speedo gear swap as well). The evaporator on SWPUWMB's 124 finally failed, so that gets fixed first. I hope to have my wagon on the lift next week or so, and will report what's inside.

Are you saying 1) that I might NOT need a custom bearing OR 2) that only a couple of us have done the later 617 matings? It wasn't clear.

What did you and the others use? The original 240 p-b?

The PB issue only applies to very late 84 and all 85 engines. In reality, thats only about 15,900 1985 engines affected vs a little over 95,200 1978-84 engines that can use the stock PB. So the chances of someone running across this issue is relatively small.

Nobody is sure as to why MB made the change so late in the game. It may have been just when they switched over to the high-stall torque converter along with the 2.88 differential. I do know that there are 13,000 or so non-turbo 300D's produced in 1984/5 and alot of them were sold with manual transmissions in Europe. However, I don't know if the smaller PB issue applies to them or if it's unique to turbo engines in the USA.

I took the stock and used a grinder to remove the excess. I ran the grinder perpendicular as much as possible to keep from over running the bearing.

thanks
 

It seems odd that they would machine a crankshaft that did not correspond to any bearing size. My understanding was that they had every combination of engine and tranny in most models, and plenty of sticks, as ForcedInduction notes. It would be unusual to change the size of the hole for combinations that did not see a shaft. :confused:

I'll start making some calls to local shops and see what I can find. Thanks for the counsel, guys.

Turbo's were never mated with 4spd manuals. I agree the size change is odd, perhaps they beefed up the internals a bit more in the 84/85? It is clear that not al 617.952 are the same.

This ain't our first rodeo...
 

You're wasting your time. Spend it by having a machine shop make a sleeve or a whole bushing to replace the PB.

Hmmm....has anyone ever measured the PB recess on a 60X engine crank? I wonder if later trannies (ie for the 601, 602, 603...) use a smaller snout on their TC's??

Knowing that the 61X engines were seeing their last days, this might have been a running production change to accomodate follow-on transmission production/manufacture.

********AZ lists same part number for an 86 2.5 and a 79 300D

Interesting. Is ******** linking to WorldPac? IF so, I'd be suspicious of the accuracy.

Couldnt you simply swap cranks from an older 617 that used that bearing size?

Now THAT would certainly be easier, wouldn't it.......:eek:

not.

tom w