Taking '70 on a road trip - should I swap trannys? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

White70C20 · 06-10-2013, 09:38 PM

I am moving to central Kansas this summer. It is about 850 miles round trip back to Iowa via interstate. My 1970 C20 has a 350/TH350/4:10 setup. It runs pretty high RPMs on the highway, let alone on the interstate. It gets kinda loud in the cab, of course the straight pipes don't help the situation much (haha). My question is: In an attept to keep RPMs lower, I have access to a rebuilt 700R4 overdrive tranny. My mechanic says it would cost $1500 total to purchase/install it. Are there other, cheaper ways to keep the RPMs lower?

I love the sound of my straight pipes, so I'd really rather not get rid of them. Besides, it was fairly loud inside even with mufflers on it.

CG · 06-10-2013, 10:03 PM

If you do change it out just make sure your road trip isn't also the shake down cruise.

*Mister-B* · 06-10-2013, 10:09 PM

Quote:

Originally Posted by White70C20

I am moving to central Kansas this summer. It is about 850 miles round trip back to Iowa via interstate. My 1970 C20 has a 350/TH350/4:10 setup. It runs pretty high RPMs on the highway, let alone on the interstate. It gets kinda loud in the cab, of course the straight pipes don't help the situation much (haha). My question is: In an attept to keep RPMs lower, I have access to a rebuilt 700R4 overdrive tranny. My mechanic says it would cost $1500 total to purchase/install it. Are there other, cheaper ways to keep the RPMs lower?

I love the sound of my straight pipes, so I'd really rather not get rid of them. Besides, it was fairly loud inside even with mufflers on it.

Unless you plan to do a lot more highway cruising after this trip, that's sure a lot of money. Yeah, the RPM's might be high, and you could go through...what? An extra $100 in gas that trip? And $1,500 is the solution? Dunno...
Posted via Mobile Device

dyrt · 06-11-2013, 09:13 AM

For 850 miles that is a bit of a toss up. However, there is also the chance that you will put in the OD trans and decide you like the ride and mileage a whole bunch more. It is certainly a popular upgrade for a reason. The only other way to lower rpms is to drive slower, tow it, or change the rear gears. The trans swap is much easier than the gear swap if you plan to put the 4.10s back in after the trip. You could always also get another rear axle to swap in with lower gears which would be a pretty quick swap. Last of all, some good sound deadening could be a quick afternoon project and may help keep the noise down for what will be quite a long drive.

Tinkermc · 06-11-2013, 10:36 AM

I have the 700r and I cruise here there and everywhere great trans, and helps with rpms and gas mileage. You could make it a trailer queen for the trip.

mrein3 · 06-11-2013, 01:14 PM

Like others are saying, do the math.

850 miles round trip. Assume 10 mpg with current setup. 85 gallons total.

The last tank I bought here was $3.859/gallon for regular unleaded.
85*3.859 = $328.02 for fuel.

Assume 30% increase with .7 OD in 700R4. 850 / 13 = 65.39 gallons. 65.39*3.859 = $252.32.

If you do it once that is $1500 you spent to save $75.70.

You need to make that trip 20 times to pay for the tranny swap.

If I was doing it once I'd stay off the freeway and keep the current tranny.

All that being said I wouldn't mind having a 700r4 in my rig to cut down on road noise associated with my 3.73s rolling down the slab at 70mph.

Dano69c10 · 06-11-2013, 02:09 PM

Quote:

Originally Posted by dyrt

For 850 miles that is a bit of a toss up. However, there is also the chance that you will put in the OD trans and decide you like the ride and mileage a whole bunch more. It is certainly a popular upgrade for a reason. The only other way to lower rpms is to drive slower, tow it, or change the rear gears. The trans swap is much easier than the gear swap if you plan to put the 4.10s back in after the trip. You could always also get another rear axle to swap in with lower gears which would be a pretty quick swap. Last of all, some good sound deadening could be a quick afternoon project and may help keep the noise down for what will be quite a long drive.

Rear axle swap < 700R tranny swap

Around here they are always on Craigslist in the $100-$150 range.

3:08, 3:4x, or 3:73 will be friendlier on the hwy.

And then you can always switch back.

**MidLifer** · 06-11-2013, 02:19 PM

You can also buy a new ring and pinion set in 3.42 (parts cost around $400) instead of swapping the whole axle. Although if you pay a mechanic to put it in, it might get costly. Never done it myself but kind of labor-intensive to get it right.

Longhorn 70 · 06-11-2013, 04:17 PM

IF you want to keep it and restore, stay with what's stock. IF you are going to use it as a daily driver, then consider the 700r4 OR if you are going to keep a STOCK small block in it, a 200-4R can be built strong and has a similar footprint as the TH350. No driveshaft cuts or mounting changes.

200-4R info can be found here.

Hubscrub · 06-11-2013, 09:36 PM

Just stay off the interstate cruise the old highways

for one trip i say no depends on yourself and the future for the truck

White70C20 · 06-11-2013, 09:47 PM

Thanks for the opinions so far.

As for keeping it stock for restoration sake, it already isn't stock. The engine was rebuilt at some point and had an Edelbrock intake, Carter AFB 4bbl. carb, chrome valve covers, and headers put on. Plus, I'm at least the 3rd person to repaint this truck as well (originaly gold, then brown, then white, and now a metalic green).

I like having the TH350 for its bulletproof reliablity and durability, but I've also read that the 700/200R4 trannys can be built to be just as durable.
I'm basicly wanting my truck to be fun to drive, but also easy to sell if I choose to get rid of it.

Longhorn 70 · 06-12-2013, 10:27 AM

I have had the same 700R4 in my C20 since 1998. It was built well when I bought it but it had a 450 HP High Torque Olds motor in front of it until recently. I had blown up several TH400s too. The 200 just takes less work to install if you find the Chevy bell housing.

MARKDTN · 06-12-2013, 03:24 PM

I would swap to a 700R4 but not just for this trip. You can also numerically lower the axle ratio and get a double-whammy improvement. The 1st gear in a 700R4 is lower than a TH350. My 83 K20 (350/700R4/3.42) got 14.5 mpg and about 17 highway before I swapped to Tuned Port.

hyatt · 06-12-2013, 03:49 PM

change it It will make your truck much more enjoyable and you engine will live longer

**special-K** · 06-12-2013, 10:14 PM

I dunno,there were interstates all over the country when these trucks were new and they got driven all over with no problems. All these Custom campers went farther than the local fishing hole. I've driven coast to coast several times in original-equipped trucks and never gave it a second thought. I really enjoyed taking my family to Santa Fe,Pagosa Springs,Mesa Verde,4 Corners,Lake Powell,Moab,Grand Canyon (N & S rim),Sedona,Petrified Forest,Meteor Crater,and back east in my '71 C/20. I loved every mile of that sweet sound. We went up and down the East Coast from the mountains to beach many times from '88-06. The original engine ran great till the day I parked it. I'd drive it 75-80 mph all day long. All I ever did was a timing chain/gears and a no-lead head job. $1,500 will take a long time to recoup saved gas money. My 4.10 truck runs 65 mph just fine. It takes 6 hours to lose an hour of travel from those going 75. I guess I'm just more patient than most these days. They say it's a virtue

**WIDESIDE72** · 06-13-2013, 01:36 AM

In my opion, my options:
1. Od swap. My choice if truck will see a lot of highway driving in the future.

2. Leave as is and drive slower by taking back roads if possible or using the right lane if tou have to use interstate on your trip to save $$$ on gas. As mentioned above, you really wont lose that much time and you see a lot more going slower.
Posted via Mobile Device

**WIDESIDE72** · 06-13-2013, 01:39 AM

I live close to a toll road that runs from Austin to San Antone. The speed limit is 85 mph. I only used the road once and it was to explore the top end of my HHR SS. Lets say it was north of 140. I dont use the road because it dump ar SA way out of the way for me and at night there is nothing out there but feral hogs. Several drivers have found that out the hard way. My ride above was during daytime. Even in my car with a 4 cyl and od and truck with duramax the increase of fuel consumption from 70 mph to 85 mph was not worth it to me.
Posted via Mobile Device

ZombieWeinerDog · 06-13-2013, 03:01 AM

i swapped my 3 speed manual for a tci 700r4. i dont know what my gas mileage was before, but from grand rapids michigan to columbus ohio, i got and average of 16 mpg with my 327. A lot better than that junky 3 speed.

**special-K** · 06-13-2013, 07:52 AM

I drove this from Maryland to Flagstaff and back. Also made several trips to Maine,Smokey Mts,Cape Hatteras,NC and once to Jensen Beach. Took a ride to Key West from there for a vacation...all on interstates. First pictures was packed for Florida w/31" tires. Second was before I left for AZ w/37" tires. Oh,no overdrive in that thing. No power steering,either.

Don Quixote · 06-15-2013, 11:29 PM

Mine's been to every state but HI. I also am pushing 440k. I run a rock-crusher and have no power steering but I just like driving it. I wouldn't change a thing, just run it. It's paid off so you can part with a few extra in gas. I keep my truck the way it is because I like the KISS method.

HalfTon · 06-16-2013, 12:16 AM

Quote:

Originally Posted by special-K

I drove this from Maryland to Flagstaff and back. Also made several trips to Cape Hatteras,NC and once to Jensen Beach,FL. Took a ride to Key West from there for a vacation. First pictures was packed for Florida. Second was before I left for AZ. Oh,no overdrive in that thing. No power steering,either.

Sorry to get off topic here but this is one of the coolest trucks I have ever laid eyes on. I know this is a chevy sight, but dear lord that mopar is sweet!!!
Posted via Mobile Device

White70C20 · 06-17-2013, 12:21 PM

Thanks for all the input guys! I just helped a buddy move this weekend. I drove my truck 120 miles (round trip) pulling a U-haul trailer and it did great, plus I only used 1/2 tank of gas! I think I'll be sticking with the TH350.
Posted via Mobile Device

luvbowties · 06-17-2013, 10:38 PM

Quote:

Originally Posted by White70C20

Thanks for all the input guys! I just helped a buddy move this weekend. I drove my truck 120 miles (round trip) pulling a U-haul trailer and it did great, plus I only used 1/2 tank of gas! I think I'll be sticking with the TH350.
Posted via Mobile Device

Put on 2 rear tires that are 10% taller, and it will be the same as changing to a 3.69:1 differential while running the shorter tires!? [4.10-10% of 4.10 = 3.69]
Sam

White70C20 · 06-17-2013, 11:43 PM

Actually, I already did that. I was running 265/75R16s and I found a set of 265/85R16s off an 80s 4x4. It helps a little bit, but it's still screaming at 70 MPH.

By the way, for those of you who have stock 3/4 tons with the 4:10 rear end, how fast do you go on the interstate? How fast will these trucks go?

Thanks!

**special-K** · 06-18-2013, 06:55 AM

What some call screaming I call purring. O/D makes 'em moan. Most aren't much for towing,either. I don't think that was mentioned here.

Thanks for the compliment,HalfTon. I really liked it,but went straight back to GM due to poor parts support by Mopar. It sat 6 weeks or more three times while I owned it waiting for parts and it wasn't even 10 years old!

06-10-2013, 09:38 PM	#1
White70C20 Registered User Join Date: Oct 2012 Location: Kansas and Iowa Posts: 349	Taking '70 on a road trip - should I swap trannys? I am moving to central Kansas this summer. It is about 850 miles round trip back to Iowa via interstate. My 1970 C20 has a 350/TH350/4:10 setup. It runs pretty high RPMs on the highway, let alone on the interstate. It gets kinda loud in the cab, of course the straight pipes don't help the situation much (haha). My question is: In an attept to keep RPMs lower, I have access to a rebuilt 700R4 overdrive tranny. My mechanic says it would cost $1500 total to purchase/install it. Are there other, cheaper ways to keep the RPMs lower? I love the sound of my straight pipes, so I'd really rather not get rid of them. Besides, it was fairly loud inside even with mufflers on it. __________________ White70C20 1970 Blue C20 - 250, 4 speed 1985 Ford Thunderbird 2005 Pontiac G6

06-10-2013, 10:03 PM	#2
CG BlahBlahBlah Join Date: Feb 2002 Location: Wa. Posts: 19,989	Re: Taking '70 on a road trip - should I swap trannys? If you do change it out just make sure your road trip isn't also the shake down cruise. __________________ … … … … … … … … ... … … … … … … … … … … …

06-11-2013, 09:13 AM	#4
dyrt Registered User Join Date: Jul 2007 Location: Yardville, NJ Posts: 144	Re: Taking '70 on a road trip - should I swap trannys? For 850 miles that is a bit of a toss up. However, there is also the chance that you will put in the OD trans and decide you like the ride and mileage a whole bunch more. It is certainly a popular upgrade for a reason. The only other way to lower rpms is to drive slower, tow it, or change the rear gears. The trans swap is much easier than the gear swap if you plan to put the 4.10s back in after the trip. You could always also get another rear axle to swap in with lower gears which would be a pretty quick swap. Last of all, some good sound deadening could be a quick afternoon project and may help keep the noise down for what will be quite a long drive.

06-11-2013, 10:36 AM	#5
Tinkermc Registered User Join Date: Jul 2011 Location: Farmville, Va Posts: 3,026	Re: Taking '70 on a road trip - should I swap trannys? I have the 700r and I cruise here there and everywhere great trans, and helps with rpms and gas mileage. You could make it a trailer queen for the trip.

06-11-2013, 01:14 PM	#6
mrein3 Registered User Join Date: Feb 2000 Location: Center City, MN, USA Posts: 3,253	Re: Taking '70 on a road trip - should I swap trannys? Like others are saying, do the math. 850 miles round trip. Assume 10 mpg with current setup. 85 gallons total. The last tank I bought here was $3.859/gallon for regular unleaded. 853.859 = $328.02 for fuel. Assume 30% increase with .7 OD in 700R4. 850 / 13 = 65.39 gallons. 65.393.859 = $252.32. If you do it once that is $1500 you spent to save $75.70. You need to make that trip 20 times to pay for the tranny swap. If I was doing it once I'd stay off the freeway and keep the current tranny. All that being said I wouldn't mind having a 700r4 in my rig to cut down on road noise associated with my 3.73s rolling down the slab at 70mph. __________________ '70 cab, '71 chassis, 383, TH350, NP205. '71 Malibu convertible '72 Malibu hard top Center City, MN

06-11-2013, 02:19 PM	#8
MidLifer Senior Member Join Date: Apr 2011 Location: South NJ Posts: 1,267	Re: Taking '70 on a road trip - should I swap trannys? You can also buy a new ring and pinion set in 3.42 (parts cost around $400) instead of swapping the whole axle. Although if you pay a mechanic to put it in, it might get costly. Never done it myself but kind of labor-intensive to get it right.

06-11-2013, 04:17 PM	#9
Longhorn 70 Registered User Join Date: Dec 2012 Location: Chandler AZ Posts: 1,149	Re: Taking '70 on a road trip - should I swap trannys? IF you want to keep it and restore, stay with what's stock. IF you are going to use it as a daily driver, then consider the 700r4 OR if you are going to keep a STOCK small block in it, a 200-4R can be built strong and has a similar footprint as the TH350. No driveshaft cuts or mounting changes. 200-4R info can be found here. __________________ 1970 Longhorn, Front Disc, 350/4 bolt, 882 heads, HEI, Edelbrock, 700R4, HO-52/4.11. 1996 Corvette, Collector Roadster, LT4, 396, 450RWHP, 6sp, 4.11/Dana44/posi 5 point roll bar And let us not grow weary of doing good, for in due season we will reap, if we do not give up. Gal 6:9

06-11-2013, 09:36 PM	#10
Hubscrub Cruzin Join Date: Dec 2009 Location: on the road Posts: 2,835	Re: Taking '70 on a road trip - should I swap trannys? Just stay off the interstate cruise the old highways for one trip i say no depends on yourself and the future for the truck __________________ Lime Wife's 67https://www.google.com/url?sa=t&rct=...wZEMODaS2d94u8 Back to the Fifties 59 https://www.google.com/url?sa=t&rct=...NAeStpydfrcj_U Proverbs 3:5,6 "Thanks to the Interstate Highway System, it is now possible to travel across the country from coast to coast without seeing anything."Charles Kuralt In memory of our first baby daughter, daddy and mommy love you. Danica Grace 6/26/14

06-11-2013, 09:47 PM	#11
White70C20 Registered User Join Date: Oct 2012 Location: Kansas and Iowa Posts: 349	Re: Taking '70 on a road trip - should I swap trannys? Thanks for the opinions so far. As for keeping it stock for restoration sake, it already isn't stock. The engine was rebuilt at some point and had an Edelbrock intake, Carter AFB 4bbl. carb, chrome valve covers, and headers put on. Plus, I'm at least the 3rd person to repaint this truck as well (originaly gold, then brown, then white, and now a metalic green). I like having the TH350 for its bulletproof reliablity and durability, but I've also read that the 700/200R4 trannys can be built to be just as durable. I'm basicly wanting my truck to be fun to drive, but also easy to sell if I choose to get rid of it. __________________ White70C20 1970 Blue C20 - 250, 4 speed 1985 Ford Thunderbird 2005 Pontiac G6

06-12-2013, 10:27 AM	#12
Longhorn 70 Registered User Join Date: Dec 2012 Location: Chandler AZ Posts: 1,149	Re: Taking '70 on a road trip - should I swap trannys? I have had the same 700R4 in my C20 since 1998. It was built well when I bought it but it had a 450 HP High Torque Olds motor in front of it until recently. I had blown up several TH400s too. The 200 just takes less work to install if you find the Chevy bell housing. __________________ 1970 Longhorn, Front Disc, 350/4 bolt, 882 heads, HEI, Edelbrock, 700R4, HO-52/4.11. 1996 Corvette, Collector Roadster, LT4, 396, 450RWHP, 6sp, 4.11/Dana44/posi 5 point roll bar And let us not grow weary of doing good, for in due season we will reap, if we do not give up. Gal 6:9

06-12-2013, 03:24 PM	#13
MARKDTN Registered User Join Date: Jan 2011 Location: Chattanooga, TN Posts: 2,159	Re: Taking '70 on a road trip - should I swap trannys? I would swap to a 700R4 but not just for this trip. You can also numerically lower the axle ratio and get a double-whammy improvement. The 1st gear in a 700R4 is lower than a TH350. My 83 K20 (350/700R4/3.42) got 14.5 mpg and about 17 highway before I swapped to Tuned Port. __________________ '83 K20-TPI '73 C10 '79 C10-ex-diesel(SOLD) '07 Tahoe(Son driving) '14 Suburban-DD '71 C10-current project

06-12-2013, 03:49 PM	#14
hyatt Registered User Join Date: Dec 2012 Location: sparta tennessee Posts: 345	Re: Taking '70 on a road trip - should I swap trannys? change it It will make your truck much more enjoyable and you engine will live longer __________________ 1946 car hauler 1948 surburban 1937 chevy sedan 1940 olds sedan (project) 1967 ss396 chevelle 1999 dually crewcab(24000 miles)

06-12-2013, 10:14 PM	#15
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,852	Re: Taking '70 on a road trip - should I swap trannys? I dunno,there were interstates all over the country when these trucks were new and they got driven all over with no problems. All these Custom campers went farther than the local fishing hole. I've driven coast to coast several times in original-equipped trucks and never gave it a second thought. I really enjoyed taking my family to Santa Fe,Pagosa Springs,Mesa Verde,4 Corners,Lake Powell,Moab,Grand Canyon (N & S rim),Sedona,Petrified Forest,Meteor Crater,and back east in my '71 C/20. I loved every mile of that sweet sound. We went up and down the East Coast from the mountains to beach many times from '88-06. The original engine ran great till the day I parked it. I'd drive it 75-80 mph all day long. All I ever did was a timing chain/gears and a no-lead head job. $1,500 will take a long time to recoup saved gas money. My 4.10 truck runs 65 mph just fine. It takes 6 hours to lose an hour of travel from those going 75. I guess I'm just more patient than most these days. They say it's a virtue __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~ Last edited by special-K; 06-12-2013 at 10:25 PM.

06-13-2013, 01:36 AM	#16
WIDESIDE72 Senior Member Join Date: Aug 2008 Location: Cedar Park, Texas Posts: 7,500	Re: Taking '70 on a road trip - should I swap trannys? In my opion, my options: 1. Od swap. My choice if truck will see a lot of highway driving in the future. 2. Leave as is and drive slower by taking back roads if possible or using the right lane if tou have to use interstate on your trip to save $$$ on gas. As mentioned above, you really wont lose that much time and you see a lot more going slower. Posted via Mobile Device

06-13-2013, 01:39 AM	#17
WIDESIDE72 Senior Member Join Date: Aug 2008 Location: Cedar Park, Texas Posts: 7,500	Re: Taking '70 on a road trip - should I swap trannys? I live close to a toll road that runs from Austin to San Antone. The speed limit is 85 mph. I only used the road once and it was to explore the top end of my HHR SS. Lets say it was north of 140. I dont use the road because it dump ar SA way out of the way for me and at night there is nothing out there but feral hogs. Several drivers have found that out the hard way. My ride above was during daytime. Even in my car with a 4 cyl and od and truck with duramax the increase of fuel consumption from 70 mph to 85 mph was not worth it to me. Posted via Mobile Device



Register or Log In To remove these advertisements.

06-13-2013, 03:01 AM	#18
ZombieWeinerDog Registered User Join Date: Oct 2008 Location: Sparta, MI Posts: 446	Re: Taking '70 on a road trip - should I swap trannys? i swapped my 3 speed manual for a tci 700r4. i dont know what my gas mileage was before, but from grand rapids michigan to columbus ohio, i got and average of 16 mpg with my 327. A lot better than that junky 3 speed. __________________ 1972 longbed- 454 1967 shortbed- 355

06-13-2013, 07:52 AM	#19
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,852	Re: Taking '70 on a road trip - should I swap trannys? I drove this from Maryland to Flagstaff and back. Also made several trips to Maine,Smokey Mts,Cape Hatteras,NC and once to Jensen Beach. Took a ride to Key West from there for a vacation...all on interstates. First pictures was packed for Florida w/31" tires. Second was before I left for AZ w/37" tires. Oh,no overdrive in that thing. No power steering,either. Attached Images __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~ Last edited by special-K; 06-18-2013 at 06:57 AM.

06-15-2013, 11:29 PM	#20
Don Quixote Registered User Join Date: May 2008 Location: Woodlawn, TN Posts: 275	Re: Taking '70 on a road trip - should I swap trannys? Mine's been to every state but HI. I also am pushing 440k. I run a rock-crusher and have no power steering but I just like driving it. I wouldn't change a thing, just run it. It's paid off so you can part with a few extra in gas. I keep my truck the way it is because I like the KISS method. __________________ Rocinante: 1972 GMC C25, 292, SM465, 14 bolt, power nothing, 440k and still handles my PCS moves Jorge: Kia Roller-skate with lots of buttons for the wife Wovoka: 2017 Indian Chief Vintage, better on gas but not much So far, this is the oldest I've ever been.

06-17-2013, 12:21 PM	#22
White70C20 Registered User Join Date: Oct 2012 Location: Kansas and Iowa Posts: 349	Re: Taking '70 on a road trip - should I swap trannys? Thanks for all the input guys! I just helped a buddy move this weekend. I drove my truck 120 miles (round trip) pulling a U-haul trailer and it did great, plus I only used 1/2 tank of gas! I think I'll be sticking with the TH350. Posted via Mobile Device __________________ White70C20 1970 Blue C20 - 250, 4 speed 1985 Ford Thunderbird 2005 Pontiac G6

06-17-2013, 11:43 PM	#24
White70C20 Registered User Join Date: Oct 2012 Location: Kansas and Iowa Posts: 349	Re: Taking '70 on a road trip - should I swap trannys? Actually, I already did that. I was running 265/75R16s and I found a set of 265/85R16s off an 80s 4x4. It helps a little bit, but it's still screaming at 70 MPH. By the way, for those of you who have stock 3/4 tons with the 4:10 rear end, how fast do you go on the interstate? How fast will these trucks go? Thanks! __________________ White70C20 1970 Blue C20 - 250, 4 speed 1985 Ford Thunderbird 2005 Pontiac G6

06-18-2013, 06:55 AM	#25
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,852	Re: Taking '70 on a road trip - should I swap trannys? What some call screaming I call purring. O/D makes 'em moan. Most aren't much for towing,either. I don't think that was mentioned here. Thanks for the compliment,HalfTon. I really liked it,but went straight back to GM due to poor parts support by Mopar. It sat 6 weeks or more three times while I owned it waiting for parts and it wasn't even 10 years old! __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~ Last edited by special-K; 06-18-2013 at 07:01 AM.

Register or Log In To remove these advertisements.