Power and Getrags

[RSchwarzli]

So, goes like this. I have 273/650 wheel power, and a South Bend 0090. I stayed with a weak clutch so that it would be my weak link so to speak.

With a HX35 going on to get egt's down, it again makes me think of my weak clutch. I have looked into a 13125 con ofe for the truck to work with potential slippage issues, but the next weak link is the gutbag. I have felt a little bit of shutter already while honking on my current setup so I imagine more power would not be good... .

My question is, how weak is the trans and what would be my weak link? Input shaft, bearings, etc? Also, just how weak is it?

Should I just stay with the 0090 or??

Need some wisdom.

Thanks!

Robert

 

[JLEONARD]

I don't think it's a simple matter of horsepower.

For example, I had 240 to the wheels and 600 ft lb, so similar to what you have. I never slipped a stock clutch. transmission was fine. 200K miles.

If my wife drove it she'd have it chattering in a month. :-laf

If my son drove it he would wreck the transmission in a month.



I think it is more a matter of how you drive and use the truck.

 

[Midnite]

I completely agree that it's dependent upon how you drive and if you tow. If it's a daily driver that doesn't tow much, then I'd say the Getrag should be fine (of course, if it's making ugly noises it might need some attention). If you tow routinely and you make use of all that power while towing, then it might be worth upgrading to a better transmission.

 

[glhs]

If you tow a lot, replace the bearings and pilot bearing every 70,000 miles before they wear out.

If you are empty, maybe every 120,000 miles.



As far as breaking the Getrag with 300 or less hp from just putting your foot into it, no, it won't happen.



I have buried my foot into this transmission with 400+ hp 100's maybe 1000's of times and it has yet to break.

Drag racing and slamming into 3rd from 2nd... ... ... ... ... ... ... ... different story.

 

[NIsaacs]

I agree with posters above. Keep the oil clean. I change at 36,000 miles, standard fill, 15/40 engine oil. All original with 310,000 miles. The little bugger is no weak sister.



Just keep doubting it like you are, drive it accordingly and it will last forever:-laf



Nick

 

[Bob Beauchaine]

Robert



I would not use 15W40 in your Getrag. Snowflake AS is just a tad warmer than Blizzard Ontario Stay with the 5W30 full synthetic - better lubrication at -30



Bob

 

[RSchwarzli]

Thanks for all of the thoughts!



As for my use, I do use it for towing, although not more than about 10K lbs. I see less towing in its future once the Crew Cab is done, but it will still tow alot (few times a month currently so less than that... ). When I do tow, I do use full power at times. Big hills and people passing me do not mix! So yes, I would consider that running hard. In 4th. With Gear Vendors on. 30 + psi.....



As for abuse, I am OK. I have my days where I am a little on the more demanding side, but for the most part nothing major as I know it does not like it. The hardest work it does is when towing. And the occasional spirited leaving a light!







Jay - I have had the current clutch chatter and rattle a bit while under WOT at around that 2000 rpm mark. Also seems to have developed a sticky spot somewhere as I have a catch in it thus requiring me to slip the clutch so as to not have the driveline jumping.





Midnight - No noises other than a chatter/rattling sound under WOT through the midrange RPM. I have been told the Getrag clutch forks rattle from vibration, but would not surprise me if that was also slippage chatter. Granted, I have never seen the tach slip while on it so maybe just forks????



glhs - Gotcha. Will do. transmission was fully rebuilt about 20K ago and new throw out bearing and pilot bearing (bronze) went in about 10K ago.



Nick - Will make sure I change it often then. This whole getrag thing is new to me so that info is appreciated.



Bob - Blizzard Ontario? :-laf You are funny!



I had put in 10W30 Amsoil Synthetic. Is that still OK?

 

[Mikey-KE7LBB]

I rebuilt mine about 3 years ago using the advise of a very knowledgeable man right here on TDR!
Just search through mysteryman's posts and you'll be amazed what you find. I rebuilt mine and have over 50k trouble free even with all the abuse!
It is a good trans if properly built and should last forever if maintained.

 

[WyattEarp]

I agree the Getrag is no whimpy transmission, otherwise it would not have been picked to been used behind the 12V Cummins, my understanding and from a neighbor it is a German transmission and i changed my fluid the other day and put new in with no issues, im going to half quart it again tomorrow get a little extra in there to keep things happy.

 

[Bob Beauchaine]

Robert



I would think 10W30 will work better than 15W40. When I was running a Getrag I tried a 5W50 so I could get the best of both worlds. It seemed to work OK but that was before overfill was found to quiet them down. I switched to the NV4500HD and was happy with how quiet it was compared to the G360.



Bob

 

[NIsaacs]

Bob, you have twice suggested that 15/40 is a bad choice. That is cool. I did not recommend anyone use it, just that I do.



I will say that 90 wt was used in manual transmissions for years, all climates. Also that Eaton and Clark recommends 50 wt. engine oil for years. I have also suggested on TDR, several times, that the light weight oils used in todays manual pick up trannys is more for fuel savings then the best interest of the transmission. I use 15/40 in all three of my trucks, it works for me.



Nick

 

[WyattEarp]

im using the 5W30 high mileage if i start towing heavy i will change to something more comperable with heat etc... so far it has done what i have asked and been quiet LOL going to put the extra 1/2 qt in today and going to pressure wash underneath and the engine as at the end of the month its going for a trip to have the KDP fixed and timing case bolts loctite

 

[Bob Beauchaine]

It was my understanding that the reason for the 5W30 recomendation was due to the tight tolerances inside the G360. It relates to the ability of the lighter fluid being able to get into these places to better lubricate.



I did not mean to suggest that you were recommending 15W40 just trying to give Robert another option in leu of his extreme weather/operating conditions he is operating in. I myself tried 5W50 to address both the colder and hotter operating conditions in the North West.



Sorry if I offended you - it was not intentional.



Bob

 

[NIsaacs]

No problem Bob, you posted good info, just that you didn't go far enough. What might be good start up gear oil for -30* might be less then ideal for normal operating temps. Gear oil is one of those compromise choices that we must make from time to time. I chose 15/40 to match the engine, less oil choices to have on hand, yet knowing I use a lot of it I always have a lot on hand.



Nick

 

[glhs]

If your going to tow that much, overfill it by a quart and run those finned aluminum transmission coolers off one or both sides.

That's what I have.

 

[RSchwarzli]

Thanks for all the responses guys!



From what I see then, by upgrading the clutch it is not going to blow the getrag unless I do something stupid!



Thanks again for all of the thoughts, opinions, and wisdom!



Robert

 

[CToney]

Robert



We would get roughly 160-180,000 kms out of a getrag with a lot of towing. We overfilled and used synthetic 5w30. The input bearing would go and then the rest of the transmission would follow. Keep rpm up so there is more hp relative to torque going in. Keep above 1700rpm. We have gone to the NV4500 as well. good luck

 

[RSchwarzli]

Thanks for the advice! Did notice the sub 1700 rattle already...

 

[Bob Beauchaine]

Hey Robert



How's the Horton working?



Bob

 

[RSchwarzli]

Installed, but the crew is STILL not on the road!



Its been 4. 5 years now since the day I pulled the door panel off to see why the window would not open..... My guess is it will be finished by spring and driving. I will let you know then Bob!



Might be time for some updated pics in a thread so everyone can see what has taken place... .