915 vs G50 trans

[tln708726]

I have replces the shift bushings but my car still goes in to 1st rough and 3rd. I'm getting ready to pull it out and put a new clutch in but my question is. Should I look at having the 915 rebuilt or buy a G50 to replace it. Will the G50 biolt right up with out modification?

[Bill Verburg]

Originally Posted by tln708726

I have replces the shift bushings but my car still goes in to 1st rough and 3rd. I'm getting ready to pull it out and put a new clutch in but my question is. Should I look at having the 915 rebuilt or buy a G50 to replace it. Will the G50 biolt right up with out modification?

It's a not a real simple or cheap swap

[Matt Monson]

tln,
You ask a very personal question and we know nothing about you. What year is this car? How is it used? What kind of miles are on the car and what is the known history of use?

Regardless, going to a G50 is going to cost 2-3 times as much as rebuilding your 915.

[tln708726]

It's a 1984 911, has 85k on it, I drive it about 3 times a week

[RWebb]

either rebuild the 915 or sell the whole car and buy an '87

[JeremyD]

or look for a 915 that's already been rebuilt, sell yours as an 85k mile example. Unless you are a ham fisted operator, 85,000 miles should not be to the point that it needs a complete rebuild. maybe check your bushings/adjustments first.

[carrera84]

Originally Posted by tln708726

Will the G50 biolt right up with out modification?

No, it will not fit in the chassis.

[Matt Monson]

Originally Posted by tln708726

It's a 1984 911, has 85k on it, I drive it about 3 times a week

Sounds like a good candidate for a few synchros, a pair of sliders and a reseal. Shouldn't cost you more than $900-1000 if you do it yourself.

Though it wouldn't hurt to change the gear oil first. Something I see time and time again on low mileage cars like this is gear oil (and engine oil) that's been left in there too long. Regardless of mileage, I tell my customers to change their gear oil every 24 months maximum. I change mine once a year. Oil has a "shelf" life in addition to mileage limits with respect to breaking down. If the oil in there is 10 years old because the mileage on the box hasn't warranted changing it, get some fresh oil in there and see what happens. This will also let you inspect the drain plug and get a more empirical idea of the wear on the box.

[Peter Zimmermann]

There are many possibilities for your 1st/3rd problem, usually it's linkage, bushings, adjustment. Which "bushings" did you replace? Are you experienced with early 911 shift linkage? Is your coupler tight? Is you shift lever perfectly vertical when the car is in neutral?

[tln708726]

I bought some of the trans fluid from our host but have not changed it yet. I've only had this car for a year but love it. I'll try changing it and see if it helps. I'm afraid the syn are worn out on 1st and 3rd. Thank you for your input all. This site is very helpful

[carrera84]

Look for Shell Spirax MB 90

[dshepp806]

Yeap,..fluid FIRST!!!!!!!!!!!

Then Pete Z's advice.....

Then follow RWebb's advice next!

Best,

[Head416]

This is from a thread asking for advice in buying a 911 with a 915 or a G50:

Originally Posted by MRM

Get one with a 915. If mere mortals were supposed to be able to shift 911s consistently without grinding the gears and wearing out the 1-2 synchros, the good Doctor would have designed the G-50 and installed it in 1965 when the 911 was born.

Don't believe the rest of the people on this board. Most think that real Porsches ended with the last of the air cooled engines. Others argue that the 89 Carrera, the last of the orginal platform, is the line that divides real Porsche 911s from modern pretenders that are currently being foisted on unsuspecting yuppies who are looking for the most fashionable cup holders to transport their double no fat mocha lattes from the golf course to the kids' soccer match.

But no, we 915 drivers know that 86 was the last year of the true Porsche and the last of the real 911s. Once it became easy to shift and tranny rebuilds were no longer included as routine maintenence, the 911 lost what it was and became something else.

So, the question is, do you want a real, true Porsche 911, or do you want some modern car that any fool can shift without wincing and counting the days and dollars till he has to break down and rebuild the tranny every time he shifts from first to second at more than 3500 RPM?

Be a man. Spare no synchro. Learn to double clutch, how to shift without engaging the synchros to spare wear and tear on the tranny and memorize UPS shipping cost from your zip code to Gary Fairbanks.

Live dangerously. Get a 915 Carrera.

This is one of my favorite posts on this site. (Although the author is misled in preferring a Carrera to an SC! )

[greg79s]

Remember that the G50 will add more weight to your car. I physically picked up a G50 with assistance recently and it was it was very heavy. Rebuilding the 915 would be economical way to go......I drive a 3.2 with a 915 (My car) and recently drove a 3.2 G50 (my father's 1987 ) The throw is shorter on the G50 and you use less energy to shift if that is what you prefer. I like the 915 better since is is lighter and has tha classic long throw shifting. You can do more with them at rebuild time if you want to make changes. Good Luck.

[island911]

Originally Posted by tln708726

...still goes in to 1st rough and 3rd. ...

that's not right. Just fix it, and you'll be happy.

[dshepp806]

can't stand the balky 915.......

[Steve@Rennsport]

Originally Posted by dshepp806

can't stand the balky 915.......

LOL,..They are only baulky when:

1) Just worn out

2) Incorrectly rebuilt

3) Worn shift coupler & bushings

4) Wrong oil

Combinations of the above.


A properly done 915 is very smooth.

[THECARREAPER]

Originally Posted by Steve@Rennsport

LOL,..They are only baulky when:

1) Just worn out

2) Incorrectly rebuilt

3) Worn shift coupler & bushings

4) Wrong oil

Combinations of the above.


A properly done 915 is very smooth.

i agree. i have had an 84 euro, an 89 anniversary edtion, my current 85 targa, and my current 87 slopenose. i go from the 85 to the 87 on a daily basis right now ( on vacation),and though they are different, i really dont like one more than the other. i just finished a major tune up, and all fluids flush on the 87, and it really, really runs and drives well now. all that is left are the brakes, and clutch bleed / flush.

my targa is very tight (58k original miles) and my other 911s had tons of miles on them.

they have distinct personalities to be sure, but they are still a pleasure to own and drive.

i say, buy one of each!

[smokintr6]

LOL,..They are only baulky when:

1) Just worn out

2) Incorrectly rebuilt

3) Worn shift coupler & bushings

4) Wrong oil

Combinations of the above.

hahahah, Steve you have just described probably 95% of all 915 transmissions in service (street cars anyway)

I probably wouldn't believe the rumor that they could be made to shift well, but my friends '81 SC shifts buttery smooth...Despite the longer throw, it may shift better than my G50! It has 80k miles on it, and to his knowlege has never been opened! The 915 can be fixed... but you will probably find there is no cheao or "easy" way out. Have it done properly!

[RWebb]

what you really want is a 901/911 transmission.

the 915 is just too modern -- other than that, I agree completely with MRM