HT740 fluid

[lostagain]

Not wanting to hijack and abuse Sean's thread, here is my question.

Clifford, I know you have been suggesting changing to 15w40 engine oil.

I see now that a little mixing with the left over Dexron is ok, according to Donald.

My transmission works fine. Except the shift up from torque converter to lock up in 1st is rough. Unless my foot is to the floor to give it power, then it is ok. Is this normal? Is the 15w40 going to smooth it out? Or is there something wrong inside the transmission?

JC

[luvrbus]

JC,that is about normal for the 740 unless the soft kit for buses was installed,you can take some of it out with adjusting the trimmer valves springs and the 15/40 will help.I'll find you a Stone/Benett and that will solve your problem, fwiw the last soft kit I purchased was close to 900 bucks they are outrageous in price now   

[eagle19952]

the shift up from torque converter to lock up in 1st is rough.
JC

mine too. especially in stop and go traffic...Houston was the worst 

[lostagain]

Yea stop and go in the city is bad because you can't always give it full throttle. I hate to hear the bang shocking the drive shaft Ujoints and the drop box. I'll change to 15w40 when I can.

How would a Stone Bennett solve the rough shift? I thought it operates the trans just like the manual lever, but with solenoids? or air?

We are camped at the Goose Island State Park North of Corpus TX. Exploring the area with the car. Did the King Ranch yesterday. Corpus Christi today. I would guess the main industry here is oil and gas, lol: oil wells everywhere on the way here, and refineries all around the city. Quite remarkable.

JC

[luvrbus]

The 740 will shift hard to lockup when the TC470 torque converter is used the TC499 converter is for bus application they are smooth as a new born baby.
The Stone won't make much different in the lockup but it sure make for smooth shifting between gear   

[RJ]

JC -

IIRC, the shift pattern for the 740 is 1U > 2U > 2L > 3L >4L, with U = Unlocked and L = Locked.

(Side note: Will you be at Quartzsite again this year?)

FWIW & HTH. . .

[luvrbus]

His shift pattern will be 1C-1L,2C-2L,3C-3L and 4C-4L (C= converter )The one you posted RJ is for a 740RS or the HT 747.

I had a 740FS that the shift pattern was 1C,2C,3L and 4L it was a economy transmission was a direct lockup in 3rd and 4th I loved that transmission it made the 8v92 shine on fuel mileage
 

[lostagain]

The only shifts I can feel are 1C to 1L, 2L, 3L and 4L. So if they are more C to L, they are real smooth and not noticeable.

Not sure about Quartzsite. Our boys are flying to New Orleans on the 17th to meet us. Then hoping to make Arcadia. Then maybe Q on the way home, since at that time of year, we might want to stay South and come West before going North and home. Wouldn't that be awesome to make 3 rallies in one trip! Dam, Arcadia, and Q.

JC

[lvmci]

JC that would be DamArcadiiQ, tom, lvmci...

[Lin]

I considered using motor oil the last time we changed the oil in our 647, but regular transmission fluid had been working fine, was recommended by United, who was doing some work for me, and I liked the idea of having a different color fluid to help identify future leaks.

[PRZNBUS]

OK, I'm totally new to buses so this probably sounds stupid but you're talking 10-40 engine oil in the transmission??

Bruce

[luvrbus]

Yep C rated oil for diesel engines not the S rated for automobile engines it's approved by Allison always has been used in older MT and HD Allisons transmissions so has Dexron 

[jackhanow]

I'm late on this and not sure, are you just replacing all or part of the oil. I always replace 1 quart of ATF with a quart of 10w30 on manual car transmissions, quieter that way and always,thinking of trying that on an automatic but never had the extra transmission just in case.