Any new info on a Diesel?..... Towing advice?

[Akita]

I'd love to hear if there is any new info on a 3/4 ton Diesel DC P/U.

I'm the original owner of a '00 Tundra 4.7 4X4. I've been a Toyota loyalist and have owned Toyota trucks since '85. ('85 and '87 p/u's, '94 T-100)
Also have an '89 V6 dually rackbody for work and got the wife/kids a Sienna.

So far the only problems with the Tundra have been the front brake rotors warping a few times (replaced), O2 sensor (recall) and I just replaced the dreaded starter (what was Toyota thinking putting it under the intake manifold). Took me almost 5 hours.
Oil changed every 4k miles and trans fluid changed every spring.
Also looking at timing belts soon if I keep it. How much will I pay Toyota to do the job?

Odometer is pushing 120k miles and I plan on doing alot more towing this year (5k lb enclosed trailer)
I searched the archives and found that the Transmision does'nt hold up well to towing.
Some failed with ALOT less miles towing less weight then mine.
I don't feel 5k lbs is alot, but it may be for this truck.
When towing my 14x7 enclosed trailer, it really has to work to get up some long steep mountain grades, but cruises at 70 fine on the flats.

I'd love to keep this truck, but I'm starting to think I'll be pushing my luck towing with it for the next 1...2...3...years.....till Toyota comes out with their "rumored" Diesel.
If Toyota had the Deisel DC out now I'd buy one.

So........... do I abuse this truck some more, hope for the best, and hope Toyota surprises us sooner then later?
Or do I bite the bullet now and go with one of the Big 3?
I'm considering an '02 Ford 7.3 powerstroke.
My freind (a Ford fan) is an ASE mechanic and has a '99 F350 and says he has no problems. He tows all summer and snowplows all winter.
He likes the Tundra for what it is, and knows Toyota reliability, but says it is'nt meant to do any serious towing.

Any advise/info?.....Thanks!

[KLS]

Towing 5000# with your truck should be no problem. You should be OK driving up mountain grades at good speed in 3rd or maybe 2nd.

I'd use synthetic ATF the next time you change it. Do you do a complete flush and refill, 16 quarts, or just a sump drain & refill, 4 quarts? Don't tow in overdrive.

You understand that you're 33% overmileage for a timing belt? They're scheduled for 90,000 miles. Our V-8 engines are one of the very few Toyota engines with a timing belt that are also interference engines. If the belt breaks engine parts hit. Big buck$. The job shouldn't be any tougher than the starter. Get a Haynes manual and see what you think.


Ken

[Akita]

Ken, I'll look into the timing belts. I know I'm overdue but have been procrastinating. Have you heard of any failing?
I would think the belt replacement would be alot more involved then the starter. The starter was a simple job, but alot of time consuming R & R.

The trans/cooling holds 16 qts?!?!? I've been draining the sump thinking that was good enough.

Also when towing, I'm doing 70-sometimes 75 on the flats, I'm in OD and only turn it off when aproaching a good incline. I think OD off all the time would kill my mileage even more at those speeds.?

Jim

[RockyMtnRay]

Originally Posted by Akita

Ken, I'll look into the timing belts. I know I'm overdue but have been procrastinating. Have you heard of any failing?
I would think the belt replacement would be alot more involved then the starter. The starter was a simple job, but alot of time consuming R & R.

No reports here of failures but several reports that the belt was in pretty poor shape. That belt also drives the water pump and there have been numerous reports of the pumps appearing to be near failure at 120K (leakage around the weep hole, mineral deposits, etc.). A timing belt replacement is also a very good time to replace the water pump.

The trans/cooling holds 16 qts?!?!? I've been draining the sump thinking that was good enough.

Yep...a flush/full replacement actually takes closer to 17 quarts...there's a lot of fluid in the torque converter that doesn't come out when you just drain the sump. Regularly draining/refilling the sump (about every 15K miles) is an alternative approach to a full flush every 30K to 60K as you replace about 5 to 6 quarts at a time this way.

Also when towing, I'm doing 70-sometimes 75 on the flats, I'm in OD and only turn it off when aproaching a good incline. I think OD off all the time would kill my mileage even more at those speeds.?

Nope, the effect on mileage of towing with OD off isn't that much...only about 1 mpg. At a given road speed, it takes the same amount of power (fuel energy) to overcome the rolling resistance and aerodynamic drag of the truck/trailer regardless of the engine RPM. Turning OD off raises engine RPM by 30%...the higher RPM does burn more fuel but only about 5% to 10% more. Comparative tests done by GM with different axle ratios in towing situations revealed that each 10% increase in the numeric ratio causes only about a 1/4 to 1/3 mpg drop in gas mileage. I recently regeared my truck from 3.91 to 4.30 (10% increase) and haven't seen any measureable change in gas mileage.

The cause of failure in nearly all the pre-03 transmissions was disintegration of the front planetary gearset. The front planetary is used when the transmission is in overdrive; it is locked solid (actually both planetaries are locked) when the transmission is in regular 3rd gear (OD off).

IMO towing any trailer over about 1000 lbs while using OD on a pre-03 Tundra...on the flats or in the hills...is a very risky proposition.

[wylcat]

Originally Posted by RockyMtnRay

IMO towing any trailer over about 1000 lbs while using OD on a pre-03 Tundra...on the flats or in the hills...is a very risky proposition.

I agree 100%, very risky!!! besides I would rather keep the tranny and pay for the gas!!!

[Akita]

Thanks for the reply Ray.
I stopped by my local dealer today and all parts are in stock for the timing belt/water pump. I just need to find the time or pay to do the job soon.
I also inquired about the rumored Diesel and the salesmen did'nt know anything about it. Go figure .They only said the new full size P/U should be out sometime this Fall. They said Toyota was sending them to a P/U training class next month and they should know more. I think I allready know more.

I'll take your advice and start towing with OD off and see how it goes. I know the newer trucks have more HP, but did they also change/mod the trans in '03?
And if I keep this truck for a few more years and the trans does go south, what kind of $$$ am I looking at? $2-3K for a rebuild?

[boody]

Are the 03' transmissions better for towing? I've got an 03' and the most I've towed with it is probably a couple thousand pounds. I've also pulled a few stumps and some trees. The transmission hasn't seemed to have any problems in OD and the torque converter dosne't unlock very often when towing a couple thousand pounds. I think everything is alright I just don't want to screw anything up.

[sewinga]

I just pulled a cargo trailer from Denver to Sacramento. I drove I-70 and was in 2nd gear(4200 rpm) for great lenghs-up to thirty miles. I still got about 11 mpg.
I was pleasantly suprised.

Also, leaving Denver on I-70 west is a formidable grade. I had od off, but with cruise control the truck went to 2nd to catch up to set speed and then go back to 3rd. Then the truck would slow down again, and go back to 2nd. Thinking about what I had learned from these threads-and especially Rocky Mountain Ray, I put the truck in 2nd-cc cancels in 2nd-and used my foot. The tundra climbed those mountains 55mph no problem.

Stephen

[RockyMtnRay]

Originally Posted by Akita

Thanks for the reply Ray.
I stopped by my local dealer today and all parts are in stock for the timing belt/water pump. I just need to find the time or pay to do the job soon.
I also inquired about the rumored Diesel and the salesmen did'nt know anything about it. Go figure .They only said the new full size P/U should be out sometime this Fall. They said Toyota was sending them to a P/U training class next month and they should know more. I think I allready know more.

I think you do too.

I'll take your advice and start towing with OD off and see how it goes. I know the newer trucks have more HP, but did they also change/mod the trans in '03?

The '05 has more HP but its peak torque is only 5 ft lbs more. However it doesn't have the torque drop off as the engine climbs above 4000 RPM like the '04s and earlier. My view is that the combo of lower tranny gearing, more gears to keep the engine closer to peak torque, and higher top end torque will make the '05s better tow vehicles when you're trying to accelerate on an on-ramp...or trying to pull a long hill in 3rd gear. For just steady towing with the OD off, there won't be any significant gain.

As for the transmission, yes there were several changes made starting with '03 but I've never found out exactly what. Apparently the internals were beefed up and the friction material on the clutches/bands was changed which caused a switch to the highly friction modified Toyota T-IV ATF. I can't recall a single report here about transmission failures in '03s and later...that is pretty strong evidence that Toyota greatly improved the transmission's durability starting in '03.

And if I keep this truck for a few more years and the trans does go south, what kind of $$$ am I looking at? $2-3K for a rebuild?

Numbers I've seen are in the range of $2500 to $4000 depending on what shop does the work and what part of the nation the work is done.

[RockyMtnRay]

Originally Posted by sewinga

I just pulled a cargo trailer from Denver to Sacramento. I drove I-70 and was in 2nd gear(4200 rpm) for great lenghs-up to thirty miles. I still got about 11 mpg.
I was pleasantly suprised.

Also, leaving Denver on I-70 west is a formidable grade. I had od off, but with cruise control the truck went to 2nd to catch up to set speed and then go back to 3rd. Then the truck would slow down again, and go back to 2nd. Thinking about what I had learned from these threads-and especially Rocky Mountain Ray, I put the truck in 2nd-cc cancels in 2nd-and used my foot. The tundra climbed those mountains 55mph no problem.

Stephen

Glad my explanations helped. Really appreciate the positive feedback.

[RockyMtnRay]

Originally Posted by boody

Are the 03' transmissions better for towing? I've got an 03' and the most I've towed with it is probably a couple thousand pounds. I've also pulled a few stumps and some trees. The transmission hasn't seemed to have any problems in OD and the torque converter dosne't unlock very often when towing a couple thousand pounds. I think everything is alright I just don't want to screw anything up.

As mentioned above, I can not recall one report of a transmission failure on an '03 (or newer).

But don't abuse it...if you start getting much TC clutch unlocking, just turn off OD and be done with it. A great deal of heat gets generated inside the transmission whenever the TC clutch is unlocked and you have the truck at high power...I've seen my transmission temperature gauge climb 30 degrees under those circumstances. The slight drop in gas mileage and increase in engine noise from turning OD off is a very small price to pay for much reduced stress on the transmission.

[RIDGEWALLOW]

Originally Posted by KLS

Towing 5000# with your truck should be no problem. You should be OK driving up mountain grades at good speed in 3rd or maybe 2nd.


Ken

I agree with Ken 100%. I previously owned a '95 Chevy 1/2ton 350ci (pre-vortec) and my 03 tundra will run circles around that chevy! I tow a 5000lb camping trailer and I am really happy with the performance of the tundra. Get yourself a good equalizer hitch, brake controller, tow with od off, and put the hammer down!
Andy

[rubio]

what about the diesel?

[alphamedic]

Ray, does this apply to a 2002 sequoia as well?

The cause of failure in nearly all the pre-03 transmissions was disintegration of the front planetary gearset. The front planetary is used when the transmission is in overdrive; it is locked solid (actually both planetaries are locked) when the transmission is in regular 3rd gear (OD off).

IMO towing any trailer over about 1000 lbs while using OD on a pre-03 Tundra...on the flats or in the hills...is a very risky proposition.[/quote]

[RockyMtnRay]

Originally Posted by alphamedic

Ray, does this apply to a 2002 sequoia as well?

The cause of failure in nearly all the pre-03 transmissions was disintegration of the front planetary gearset. The front planetary is used when the transmission is in overdrive; it is locked solid (actually both planetaries are locked) when the transmission is in regular 3rd gear (OD off).

IMO towing any trailer over about 1000 lbs while using OD on a pre-03 Tundra...on the flats or in the hills...is a very risky proposition.

[/quote]

Yep, same tranny.