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Need Advice…

1737 Views 72 Replies 10 Participants Last post by  mustangmarty1967
I’m pulling a trailer with an old Mustang chassis on it on level ground about 55 mph in 5th gear. I started hearing a high pitched hum from the front of the truck and smelled a slight scent of something burning. I let up a bit. Then a sudden grinding sound for a second until I let up completely. Thought it might be the turbo blowing again. Put it into 4th and nursed it in to a Walmart parking lot. I pulled the BHAF and hose to check the turbo. It seems fine. Belt seems okay. It starts up fine and sounds fine. There is engine oil leaking from the where the engine and tranny bell housing come together. I’m wondering if the clutch is going out. Has this happened to anyone else? Any ideas what it could be? I really need to get this car moved today.
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If you don't use your truck in such a manner that it needs the upgrade (or have plans to use your truck in such a manner), then the upgrade is a waste of money.
I lost my 5th gear, driving 70 with the cruise control on, no load when the truck had less than 100k on it. I had not started towing commercially at that time and the heaviest trailer I owned was about 10,000 pounds. I had not done a thing to the engine because it was still under warranty. Fast forward to the 11 following transmissions. None of them had a fifth gear come off, all had a fully splined shaft.

I have done extensive research on this. I own one. I have talked to many people that own them. There is no 100% permanent fix for this. It mostly comes down to the driver. As long as you don't turn up big power and tow heavy or lug it in 5th gear it most likely will be fine. If you do any of that it will eventually come off due to the inferior design of the splines. I have seen these go several hundred thousand miles without problem. Too much back-and-forth stress on the gear causes it to move on the shaft eventually loosening ANYTHING that tries to hold it.
Your research is faulty and nothing you posted is true other than the design problem with the stock shaft. I doubt anyone can say for certain what the cause of the nut backing off is.

A hackneyed response.

I have not had experience yet with the fully splined shaft....
Yet you post nonsense.
"nonsence" ??? YOU are the COMPLETE IDIOT that posted "torque multiplication" from a automatic transmission with only 4 gears would work as well as a transmission with many more gears for towing heavy weight and then went out and bought a new truck with 8 gears! Only a CLOWN would make a statement like that so go back to your corner and put you dunce cap on! You won the IDIOT OF THE YEAR award with that one!!! LOL!
The only thing that 8 gears does better than the 3 gears in my other automatic pickup is it keeps the engine at it's most efficient rpm while accelerating and while driving. The top two gears are overdrive, the 3 speed transmission doesn't have an overdrive gear. The new one is obviously stronger, but only because there is almost 50 years of technology in my new truck. Both pickups pull my 4000 pound boat and trailer with ease. I still have the old pickup. I bought the new pickup for my wife to drive because of it's creature comforts. Regardless, that has nothing to do with an NV4500 fully splined shaft. Your red herring is moot and you don't have a clue.
Maybe with that trans, but he has no understanding at all about gearing.

Again, look at the gear ratios of the 8 speed and the 3 speed auto. Low gear is more then TWICE as low as the 3 speed. Perfect for towing, but you "bought it for your wife to drive" !!! COMPLETE IDIOT. And no the 3 speed can't even come close to the 8 speed in towing. Manufactures just add more and lower gears for no reason? Tell that non sence to a semi truck driver. If you are really that STUPID you should get out of the towing business.
Open your mouth, change feet. My old pickup has a carbureted 350 that makes about 250HP. My new Hemi is advertised at 395 HP yet both trucks pull my boat up the ramp the same. If you ever find someone who would marry you tell her she is an idiot if she wants a new vehicle. Her pickup is no more perfect for towing than mine, it just has a bigger cab, a nicer stereo, a better heater and an A/C that works.
How many class 8 trucks have you driven to be such an expert?
100% COMPLETE STUPIDY! Even a kid on a bicycle knows the difference between a 3 speed and a 10 speed. But you bought a new 8 speed for "comfort". "3 gears is enough with "torque multiplication" LOL! Maybe you should let the transmission manufactures know they "only need 3 gears" IDIOT!!!
My '67 Chev came from the factory with a 327 and a 2 speed automatic. It has a GVWR of 7500 pounds. My '19 Ram has almost double the HP and four time as many forward gears, yet it's GVWR is only 6900 pounds. How do you explain the lower rating?

Try to respond like an adult without violating the forum rules this time.
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Fully spliced shaft is the most permanent fix you can get. If your dumb enough to lug ANY truck something is going to break. Thats basic science proven over the last 70 years. Don't believe me or games call the pros.
It is speculation that lugging causes the gear to come off. I know it wasn't the case when mine did.

It is GAmes, first initial, last name. Thankyou.
GVWR is carying weight, not towing weight. But you wont understand that so go tell the transmission manufactures that they "really only need 2 gears" not 8 like the one you bought. IDIOT! o_O
So much for responding like an adult. But weight is weight, pulling or carrying. Your answer doesn't carry water.
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2 gears same as 8 LOL!!!!!!!! IDIOT!
Just where did I say that two is the same as eight? I explained why eight is better, but it isn't why you think it is. Two work very well behind the lower HP engine because of torque multiplication. That's the fact.
There is a difference between and 8 speed automatic transmission and a 2 speed automatic transmission, and I know why 8 is better than 2. I tried to explain it to you, but it's a waste of energy. I don't need to tell myself anything different.

You are not worthy of any more of my time.
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No way is there 2 quarts in the bottom if you used a bottom PTO cover bolt to drain it. If my memory serves me correctly that bolt hole is lower than the bottom of the tail shaft. If it isn't, put a drain pan under it while you are pulling it apart.
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