700R4 shift points?

[bmiszuk]

My 700R4 shifts into 4th gear (overdrive) around 35mph in town. This feels like it's too soon and is lugging the engine, but maybe I've been driving too many gas engines lately smile.gif . Is it typical, or should I put the shifter into 3rd around town?

Generally I'm pretty easy on the pedal. I'm more interested in fuel economy than acceleration. I've heard that the overdrive is a weak point on the 700R4 and I should not use it around town, but am not sure if that's true or not.

[dieselbegreat]

How is the shift quality all around? A perfect shift has been defined as one that you really can't say much about. Not slide-shifting, but not hard. Not early, not late. Is it the original 83 trans? Is it a vacuum or throttle cable setup? Provided you have the correct governor for your vehicle and axle ratio, an adjustment can be made to adjust the shift points and quality, but make slight incremental adjustments only. If your shifts are firm and still early, a governor change may be necessary.

Re driving around town in OD, I owned an 87 Caprice Police Package and it specified using Drive around town, and saving OD for the highway. And some 700's are valved to lock-up the torque converter in either 2nd, 3rd or 4th gear. I'd say that's good for fuel economy. Again, it all depends on the application. For example, the Police governor allows the engine to shift at around 5000 rpm at WOT which is totally unacceptable for a diesel!

[bmiszuk]

Tranny was rebuilt in '96 or thereabouts. The shifts feel okay, there's no obvious slipping going on. It may not be perfect but it's an older truck and I don't sense anything terribly unusual going on. Just seems to shift to 4th quicker than I expected.

[CleviteKid]

If you are light on the go-pedal, a shift into 4th at 35 mph is typical. When you are accelerating hard, at what MPH is the shift to 4th?

If you are also going into torque converter clutch (TCC) lockup at the same time, the shift to 4th is pretty disconcerting. I have put a switch on the dash to prevent TCC lockup around town, and the truck is much more driveable in traffic without the TCC lockup. Out on the open highway, I flip the switch and let the TCC do its thing.

Dr. Lee :cool:

[bmiszuk]

When I got on it harder, I got shifts at 35, 40, and then (lockup?) at 45. I assume the final shift I feel is TC lockup. Do you disable yours just to improve drivability or does it have a negative effect on the transmission to lockup around town?

[Dieselboy]

I interrupted the power to my TC lockup as well. It's mainly for ease of driving in town. Don't keep it unlocked too long on the highway as tranny temps will soar past 200 in short order.

Unlocked for driving in town, and lockup up for highway time.

[bmiszuk]

Is it tough on the transmission to have the TCC locking up around town?

[Stray Cat]

700R4 should shift 1st-2nd around 15MPH(conservative) to 17MPH (aggressive). Because you have only one adjustment, the TV, on a 700R4, you can only set it one way. I have found that the 1st-2nd shift is the easiest to gauge and most sensitive to change in the TV. Once you get the 1st-2nd set, all the others are pretty good. Another option is to ge a shift kit. I put one in my 700R4 and love the results! I used the "towing" option of the kit.

[twaddle]

Hi Guys,
Can anyone recommend a good reliable source for a rebuilt 700R4 to install into an ex military M1008 (1 1/4 ton K30 with 6.2 diesel) in place of the 3 speed TH400.

Thanks

Jim Twaddle
Biggar, Scotland

[Dieselboy]

I like my Art-Carr. 25,000 miles and still going strong. I got the 400 hp towing special - 30 spline input, late style valve body, 1200 stall converter.

I didn't like my six Raptor transmissions from Performance Transmissions in Bossier, LA. They never made it past 2000 miles.

[Stray Cat]

I agree that the PATC (Performace Automotive Transmission Center) trans are BAD! This is the third time I have given this opinion on the Diesel Page, and I will every time it is pertinent. Their web-site is impressive, but their product is poor! I spent thousands of dollars and much down-time because of their product. When I finally had a local, honest, transmission shop get the trans running right (after sending it back to PATC twice), they said that it was a worn out trans with a few fancy parts...not a rebuild that any reputable trans shop would send out. Please...don't be impressed with the great web-site...the product is junk, and you will regret it if you buy it!

[twaddle]

Have any of you guys tried "Mad Dog Lou" for 6.2 application for his rebuilt 700R4?
Any feedback would be most welcome.

Thanks

Jim email <jim@jimmyt.plus.com>
Biggar, Scotland